diff --git a/.env.example b/.env.example
index e7266227..ce10d499 100644
--- a/.env.example
+++ b/.env.example
@@ -124,6 +124,19 @@ ANTHROPIC_API_KEY=
 # Enterprise license (SSO, token-auth, no-tracking)
 LICENSE_KEY=
 
+# ──────────────────────────────────────────────
+# Optional — Upload file size limits (megabytes)
+# ──────────────────────────────────────────────
+# Unset = built-in defaults. Set on both api and dashboard (compose passes these through).
+# Also raise any reverse-proxy body-size limit (nginx client_max_body_size, etc.) if you go high.
+# UPLOAD_MAX_DOCUMENT_MB=5          # Course lesson documents (PDF, DOCX, DOC)
+# UPLOAD_MAX_IMAGE_MB=5               # Avatars, media library, editor images
+# UPLOAD_MAX_VIDEO_MB=800             # Lesson video uploads
+# UPLOAD_MAX_EXERCISE_FILE_MB=2       # Student assignment file-upload questions
+# UPLOAD_MAX_AGENT_DOCUMENT_MB=5      # AI assistant document uploads
+# UPLOAD_MAX_LANDING_IMAGE_MB=0.5     # Org landing page cover images
+# UPLOAD_MAX_THUMBNAIL_MB=5           # Media thumbnail uploads
+
 # Custom branding (meta tags)
 # PUBLIC_APP_TITLE=My Learning Platform
 # PUBLIC_APP_DESCRIPTION=A flexible LMS
diff --git a/README.md b/README.md
index 2c7d46ab..667a8cfb 100644
--- a/README.md
+++ b/README.md
@@ -163,6 +163,7 @@ The repository also contains shared packages under `packages/` (for example `pac
 
    - Running the background workers? Also create `apps/jobs/.env` (e.g. `cp apps/api/.env apps/jobs/.env`); it needs `REDIS_URL`. The `packages/db/.env` used by the DB scripts is set up in step 6.
    - Optional for self-hosted Enterprise-only features (SSO, token-auth, no-tracking): set `LICENSE_KEY` in `apps/api/.env`.
+   - Optional upload size limits: set matching `UPLOAD_MAX_*_MB` values in **both** `apps/api/.env` and `apps/dashboard/.env` (see `apps/api/.env.example`). Defaults are 5 MB documents, 2 MB assignment files, 800 MB videos.
 
 6. Start local infrastructure for API (Postgres + Redis) and seed the DB:
 
@@ -249,7 +250,7 @@ cp .env.example .env   # copy env template, edit for your domain
 
 The script reads root `.env` via `docker compose --env-file .env` and auto-generates a secure `PRIVATE_SERVER_KEY` (and `BETTER_AUTH_SECRET`) when missing.
 
-See [`.env.example`](.env.example) for the full list of environment variables with required/optional grouping, and [`docker/docs/SELF_HOST.md`](docker/docs/SELF_HOST.md) for the complete Docker self-hosting guide.
+See [`.env.example`](.env.example) for the full list of environment variables with required/optional grouping, and [`docker/docs/SELF_HOST.md`](docker/docs/SELF_HOST.md) for the complete Docker self-hosting guide. To raise upload caps (documents, videos, assignment files), set the `UPLOAD_MAX_*_MB` vars in `.env` — see the [docs](https://docs.classroomio.com/docs/self-hosted/docker#optional--upload-file-size-limits).
 
 ## Publishing
 
diff --git a/apps/api/.env.example b/apps/api/.env.example
index d7a1140f..0c555ed5 100644
--- a/apps/api/.env.example
+++ b/apps/api/.env.example
@@ -89,6 +89,15 @@ MOONSHOT_API_KEY=""
 # AGENT_MAX_FETCHES_PER_CONVERSATION=15
 # AGENT_MAX_FETCHES_PER_ORG_PER_DAY=500
 
+# Upload file size limits (megabytes). Set these on both API and dashboard for self-hosted installs.
+# UPLOAD_MAX_DOCUMENT_MB=5
+# UPLOAD_MAX_IMAGE_MB=5
+# UPLOAD_MAX_VIDEO_MB=800
+# UPLOAD_MAX_EXERCISE_FILE_MB=2
+# UPLOAD_MAX_AGENT_DOCUMENT_MB=5
+# UPLOAD_MAX_LANDING_IMAGE_MB=0.5
+# UPLOAD_MAX_THUMBNAIL_MB=5
+
 # Tinybird event tracking for AI observability (optional — silently skipped when not set)
 # TINYBIRD_TOKEN=""
 # TINYBIRD_BASE_URL="https://api.tinybird.co"
\ No newline at end of file
diff --git a/apps/api/src/constants/upload.ts b/apps/api/src/constants/upload.ts
index c9e2d23a..daeea326 100644
--- a/apps/api/src/constants/upload.ts
+++ b/apps/api/src/constants/upload.ts
@@ -1,7 +1,15 @@
+import { getUploadLimits } from '@cio/core/config/upload-limits';
+
+const limits = getUploadLimits();
+
 // API-specific constants (file size limits)
-export const MAX_FILE_SIZE = 800 * 1024 * 1024; // 800MB
-export const MAX_DOCUMENT_SIZE = 5 * 1024 * 1024; // 5MB
-export const MAX_IMAGE_SIZE = 5 * 1024 * 1024; // 5MB
+export const MAX_FILE_SIZE = limits.videoBytes;
+export const MAX_DOCUMENT_SIZE = limits.documentBytes;
+export const MAX_IMAGE_SIZE = limits.imageBytes;
+export const MAX_EXERCISE_FILE_SIZE = limits.exerciseFileBytes;
+export const MAX_AGENT_DOCUMENT_SIZE = limits.agentDocumentBytes;
+
+export { getUploadLimits };
 
 // API-specific constants (bucket names)
 export const BUCKET_NAME = {
diff --git a/apps/api/src/routes/agent/agent.ts b/apps/api/src/routes/agent/agent.ts
index a6511912..ff8c5f49 100644
--- a/apps/api/src/routes/agent/agent.ts
+++ b/apps/api/src/routes/agent/agent.ts
@@ -6,6 +6,7 @@ import { orgAdminMiddleware } from '@api/middlewares/org-admin';
 import { authOrApiKeyMiddleware } from '@api/middlewares/auth-or-api-key';
 import { b64EnvelopeRewrite } from '@api/middlewares/b64-envelope';
 import { handleError, AppError } from '@api/utils/errors';
+import { MAX_AGENT_DOCUMENT_SIZE } from '@api/constants/upload';
 import { zValidator } from '@hono/zod-validator';
 import { streamText, stepCountIs, convertToModelMessages } from 'ai';
 import {
@@ -171,7 +172,7 @@ const agentCoreRouter = new Hono()
     } catch (error) {
       if (error instanceof AppError) {
         if (error.statusCode === 413) {
-          return c.json({ success: false, error: 'file_too_large', maxSize: 5242880 }, 413);
+          return c.json({ success: false, error: 'file_too_large', maxSize: MAX_AGENT_DOCUMENT_SIZE }, 413);
         }
 
         if (error.statusCode === 415) {
diff --git a/apps/api/src/routes/course/presign.ts b/apps/api/src/routes/course/presign.ts
index 7c8fcd56..8e7fd7ae 100644
--- a/apps/api/src/routes/course/presign.ts
+++ b/apps/api/src/routes/course/presign.ts
@@ -14,6 +14,19 @@ import {
 import { Hono } from '@api/utils/hono';
 import { authMiddleware } from '@api/middlewares/auth';
 import { generateFileKey } from '@cio/core/utils/upload';
+import { AppError } from '@api/utils/errors';
+import { MAX_DOCUMENT_SIZE, MAX_FILE_SIZE } from '@api/constants/upload';
+
+/**
+ * Advisory check on client-reported `fileSize`. Upload bytes go directly to object storage
+ * via the presigned PUT URL, so omitting `fileSize` (or understating it) bypasses this guard.
+ * Real enforcement requires storage-side policies (bucket max object size, etc.).
+ */
+function assertPresignFileSizeWithinLimit(fileSize: number | undefined, maxBytes: number): void {
+  if (fileSize != null && fileSize > maxBytes) {
+    throw new AppError(`File size exceeds maximum of ${maxBytes / 1024 / 1024}MB`, 'FILE_TOO_LARGE', 413);
+  }
+}
 
 // Response schemas for OpenAPI documentation
 const PresignUploadResponse = {
@@ -68,7 +81,10 @@ export const presignRouter = new Hono()
     async (c) => {
       const body = c.req.valid('json');
 
-      const { fileName, fileType } = body;
+      const { fileName, fileType, fileSize } = body;
+
+      assertPresignFileSizeWithinLimit(fileSize, MAX_FILE_SIZE);
+
       const fileKey = generateFileKey(fileName);
 
       const presignedUrl = await generateVideoUploadPresignedUrl(fileKey, fileType);
@@ -108,7 +124,10 @@ export const presignRouter = new Hono()
     async (c) => {
       const body = c.req.valid('json');
 
-      const { fileName, fileType } = body;
+      const { fileName, fileType, fileSize } = body;
+
+      assertPresignFileSizeWithinLimit(fileSize, MAX_DOCUMENT_SIZE);
+
       const fileKey = generateFileKey(fileName);
 
       const presignedUrl = await generateDocumentUploadPresignedUrl(fileKey, fileType);
diff --git a/apps/dashboard/.env.example b/apps/dashboard/.env.example
index 31989e75..c5ed85f0 100644
--- a/apps/dashboard/.env.example
+++ b/apps/dashboard/.env.example
@@ -52,3 +52,12 @@ PUBLIC_SENTRY_ENVIRONMENT=production
 PUBLIC_SENTRY_TRACES_SAMPLE_RATE=0
 PUBLIC_SENTRY_REPLAYS_SESSION_SAMPLE_RATE=0
 PUBLIC_SENTRY_REPLAYS_ON_ERROR_SAMPLE_RATE=1
+
+# Upload file size limits (megabytes). Must match apps/api/.env for self-hosted installs.
+# UPLOAD_MAX_DOCUMENT_MB=5
+# UPLOAD_MAX_IMAGE_MB=5
+# UPLOAD_MAX_VIDEO_MB=800
+# UPLOAD_MAX_EXERCISE_FILE_MB=2
+# UPLOAD_MAX_AGENT_DOCUMENT_MB=5
+# UPLOAD_MAX_LANDING_IMAGE_MB=0.5
+# UPLOAD_MAX_THUMBNAIL_MB=5
diff --git a/apps/dashboard/src/lib/features/course/api/presign.svelte.ts b/apps/dashboard/src/lib/features/course/api/presign.svelte.ts
index 7dd017f9..32df50ad 100644
--- a/apps/dashboard/src/lib/features/course/api/presign.svelte.ts
+++ b/apps/dashboard/src/lib/features/course/api/presign.svelte.ts
@@ -15,11 +15,11 @@ export class PresignApi extends BaseApiWithErrors {
    * Gets a presigned upload URL for a document.
    * @returns { url, fileKey } on success
    */
-  async getDocumentUploadUrl(fileName: string, fileType: string) {
+  async getDocumentUploadUrl(fileName: string, fileType: string, fileSize?: number) {
     const result = await this.execute<DocumentUploadPresignRequest>({
       requestFn: () =>
         classroomio.course.presign.document.upload.$post({
-          json: { fileName, fileType }
+          json: { fileName, fileType, ...(fileSize != null && fileSize > 0 ? { fileSize } : {}) }
         }),
       logContext: 'getting document upload URL'
     });
@@ -47,11 +47,11 @@ export class PresignApi extends BaseApiWithErrors {
    * Gets a presigned upload URL for a video.
    * @returns { url, fileKey } on success
    */
-  async getVideoUploadUrl(fileName: string, fileType: string) {
+  async getVideoUploadUrl(fileName: string, fileType: string, fileSize?: number) {
     const result = await this.execute<VideoUploadPresignRequest>({
       requestFn: () =>
         classroomio.course.presign.video.upload.$post({
-          json: { fileName, fileType }
+          json: { fileName, fileType, ...(fileSize != null && fileSize > 0 ? { fileSize } : {}) }
         }),
       logContext: 'getting video upload URL'
     });
diff --git a/apps/dashboard/src/lib/features/course/components/exercise/edit-mode.svelte b/apps/dashboard/src/lib/features/course/components/exercise/edit-mode.svelte
index 4811116a..9abec214 100644
--- a/apps/dashboard/src/lib/features/course/components/exercise/edit-mode.svelte
+++ b/apps/dashboard/src/lib/features/course/components/exercise/edit-mode.svelte
@@ -44,8 +44,11 @@
   import SectionEditor from './section-editor.svelte';
   import type { Question } from '$features/course/types';
   import type { ExerciseEditorErrors } from './store';
+  import { getResolvedUploadLimits } from '$lib/utils/config/upload-limits-context';
 
   const flipDurationMs = 200;
+  const uploadLimits = getResolvedUploadLimits();
+  const platformMaxFileSizeMb = uploadLimits.exerciseFileMb;
   const initialQuestionsLength = $questionnaire.questions.length;
   type QuestionDndEvent = CustomEvent<{ items: Question[] }>;
 
@@ -390,6 +393,7 @@
           mode: 'edit',
           question: toExerciseQuestionModel(question),
           labels: questionLabels,
+          platformMaxFileSizeMb,
           onImageUpload: uploadImage
         }}
         onQuestionChange={(nextQuestion) => onSharedQuestionChange(question.id, nextQuestion)}
diff --git a/apps/dashboard/src/lib/features/course/components/exercise/view-mode.svelte b/apps/dashboard/src/lib/features/course/components/exercise/view-mode.svelte
index ef09b0e4..6dbd8c97 100644
--- a/apps/dashboard/src/lib/features/course/components/exercise/view-mode.svelte
+++ b/apps/dashboard/src/lib/features/course/components/exercise/view-mode.svelte
@@ -54,6 +54,7 @@
   import ChevronLeftIcon from '@lucide/svelte/icons/chevron-left';
   import ChevronRightIcon from '@lucide/svelte/icons/chevron-right';
   import type { Question } from '$features/course/types';
+  import { getResolvedUploadLimits } from '$lib/utils/config/upload-limits-context';
 
   interface Props {
     preview?: boolean;
@@ -65,6 +66,9 @@
 
   let { preview = false, exerciseId = '', isFetchingExercise = false, mySubmissions = [] }: Props = $props();
 
+  const uploadLimits = getResolvedUploadLimits();
+  const platformMaxFileSizeMb = uploadLimits.exerciseFileMb;
+
   let isSubmitting = $state(false);
   /** When true, do not re-apply a past submission over a fresh take (Try again). */
   let skipHydrateFromSubmissions = $state(false);
@@ -305,7 +309,8 @@
       file.type as
         | 'application/pdf'
         | 'application/vnd.openxmlformats-officedocument.wordprocessingml.document'
-        | 'application/msword'
+        | 'application/msword',
+      file.size > 0 ? file.size : undefined
     );
     if (!uploadResult) {
       throw new Error('Failed to get upload URL');
@@ -946,6 +951,7 @@
             answer: $questionnaireMetaData.answers[sectionQuestionKey],
             labels: questionLabels,
             disabled: isSubmitting,
+            platformMaxFileSizeMb,
             onFileUpload: handleFileUpload,
             onVideoRecordingUpload: handleVideoRecordingUpload
           }}
@@ -1002,6 +1008,7 @@
                   answer: sharedCurrentAnswer,
                   labels: questionLabels,
                   disabled: isSubmitting,
+                  platformMaxFileSizeMb,
                   onFileUpload: handleFileUpload,
                   onVideoRecordingUpload: handleVideoRecordingUpload
                 }}
diff --git a/apps/dashboard/src/lib/features/course/components/lesson/document/add-document-modal.svelte b/apps/dashboard/src/lib/features/course/components/lesson/document/add-document-modal.svelte
index 284bf7bb..5a6066a1 100644
--- a/apps/dashboard/src/lib/features/course/components/lesson/document/add-document-modal.svelte
+++ b/apps/dashboard/src/lib/features/course/components/lesson/document/add-document-modal.svelte
@@ -14,6 +14,7 @@
   import * as Dialog from '@cio/ui/base/dialog';
   import * as FileDropZone from '@cio/ui/custom/file-drop-zone';
   import type { FileRejectedReason } from '@cio/ui/custom/file-drop-zone';
+  import { getResolvedUploadLimits } from '$lib/utils/config/upload-limits-context';
 
   interface Props {
     lessonId?: string;
@@ -34,7 +35,8 @@
     'application/msword'
   ];
 
-  const MAX_DOCUMENT_SIZE = 5 * 1024 * 1024; // 5MB
+  const uploadLimits = getResolvedUploadLimits();
+  const maxDocumentSize = uploadLimits.documentBytes;
 
   const documentUploader = new DocumentUploader();
 
@@ -58,9 +60,9 @@
       return $t('course.navItem.lessons.materials.tabs.document.file_type_error');
     }
 
-    if (file.size > MAX_DOCUMENT_SIZE) {
+    if (file.size > maxDocumentSize) {
       return $t('course.navItem.lessons.materials.tabs.document.file_size_error', {
-        size: formatFileSize(MAX_DOCUMENT_SIZE)
+        size: formatFileSize(maxDocumentSize)
       });
     }
 
@@ -87,7 +89,7 @@
     if (opts.reason === 'Maximum file size exceeded') {
       snackbar.error(
         $t('course.navItem.lessons.materials.tabs.document.file_size_error', {
-          size: formatFileSize(MAX_DOCUMENT_SIZE)
+          size: formatFileSize(maxDocumentSize)
         })
       );
     } else if (opts.reason === 'File type not allowed') {
@@ -259,7 +261,7 @@
             accept=".pdf,.docx,.doc,application/pdf,application/vnd.openxmlformats-officedocument.wordprocessingml.document,application/msword"
             maxFiles={1}
             fileCount={0}
-            maxFileSize={MAX_DOCUMENT_SIZE}
+            maxFileSize={maxDocumentSize}
             onUpload={handleFilesUpload}
             onFileRejected={handleFileRejected}
           >
diff --git a/apps/dashboard/src/lib/features/course/components/lesson/video/upload-video.svelte b/apps/dashboard/src/lib/features/course/components/lesson/video/upload-video.svelte
index 8e31eaa6..1f5dff36 100644
--- a/apps/dashboard/src/lib/features/course/components/lesson/video/upload-video.svelte
+++ b/apps/dashboard/src/lib/features/course/components/lesson/video/upload-video.svelte
@@ -14,6 +14,7 @@
   import { mediaApi } from '$features/media/api';
   import { JobPoller, jobsApi, type MediaJobEnvelope } from '$features/jobs';
   import { onDestroy } from 'svelte';
+  import { getResolvedUploadLimits } from '$lib/utils/config/upload-limits-context';
 
   const ADD_VIDEO = 'course.navItem.lessons.materials.tabs.video.add_video';
   const PROCESSING_BASE = `${ADD_VIDEO}.processing`;
@@ -50,6 +51,9 @@
 
   const isDisabled = $derived($lessonVideoUpload.isUploading || $isFreePlan);
 
+  const uploadLimits = getResolvedUploadLimits();
+  const maxVideoSize = uploadLimits.videoBytes;
+
   const videoUploader = new VideoUploader();
   const mediaUploader = new MediaUploader();
 
@@ -401,7 +405,7 @@
         accept="video/*"
         maxFiles={1}
         fileCount={0}
-        maxFileSize={800 * FileDropZone.MEGABYTE}
+        maxFileSize={maxVideoSize}
         onUpload={handleUpload}
         {onFileRejected}
       >
diff --git a/apps/dashboard/src/lib/features/media/components/edit-asset-dialog.svelte b/apps/dashboard/src/lib/features/media/components/edit-asset-dialog.svelte
index 21e44365..ec26afa5 100644
--- a/apps/dashboard/src/lib/features/media/components/edit-asset-dialog.svelte
+++ b/apps/dashboard/src/lib/features/media/components/edit-asset-dialog.svelte
@@ -12,6 +12,7 @@
   import { snackbar } from '$features/ui/snackbar/store';
   import { t } from '$lib/utils/functions/translations';
   import { uploadImage } from '$lib/utils/services/upload';
+  import { getResolvedUploadLimits } from '$lib/utils/config/upload-limits-context';
 
   interface Props {
     open?: boolean;
@@ -22,7 +23,8 @@
 
   type AssetStatusValue = 'active' | 'archived';
 
-  const THUMBNAIL_MAX_SIZE = 5 * FileDropZone.MEGABYTE;
+  const uploadLimits = getResolvedUploadLimits();
+  const thumbnailMaxSize = uploadLimits.thumbnailBytes;
 
   let { open = $bindable(false), asset = null, isSaving = false, onSave = async () => {} }: Props = $props();
 
@@ -126,7 +128,7 @@
               accept={FileDropZone.ACCEPT_IMAGE}
               maxFiles={1}
               fileCount={0}
-              maxFileSize={THUMBNAIL_MAX_SIZE}
+              maxFileSize={thumbnailMaxSize}
               onUpload={handleThumbnailFilesUpload}
               onFileRejected={handleThumbnailRejected}
             >
diff --git a/apps/dashboard/src/lib/features/media/components/manage-thumbnails-dialog.svelte b/apps/dashboard/src/lib/features/media/components/manage-thumbnails-dialog.svelte
index c431a261..8b936d3f 100644
--- a/apps/dashboard/src/lib/features/media/components/manage-thumbnails-dialog.svelte
+++ b/apps/dashboard/src/lib/features/media/components/manage-thumbnails-dialog.svelte
@@ -14,6 +14,7 @@
   import { t } from '$lib/utils/functions/translations';
   import { uploadImage } from '$lib/utils/services/upload';
   import { classroomio } from '$lib/utils/services/api';
+  import { getResolvedUploadLimits } from '$lib/utils/config/upload-limits-context';
 
   function buildHlsUrl(asset: OrganizationAsset): string | null {
     if (!asset.hlsManifestKey) return null;
@@ -32,7 +33,8 @@
     onThumbnailSaved?: (asset: OrganizationAsset) => void;
   }
 
-  const THUMBNAIL_MAX_SIZE = 1 * FileDropZone.MEGABYTE;
+  const uploadLimits = getResolvedUploadLimits();
+  const thumbnailMaxSize = uploadLimits.thumbnailBytes;
   const REGEN_POLL_INTERVAL_MS = 2000;
   const REGEN_POLL_TIMEOUT_MS = 60_000;
   const SLOT_KEYS = ['start', 'middle', 'end'] as const;
@@ -289,7 +291,7 @@
                 accept={FileDropZone.ACCEPT_IMAGE}
                 maxFiles={1}
                 fileCount={0}
-                maxFileSize={THUMBNAIL_MAX_SIZE}
+                maxFileSize={thumbnailMaxSize}
                 onUpload={handleCustomUpload}
                 onFileRejected={handleUploadRejected}
               >
diff --git a/apps/dashboard/src/lib/features/ui/upload-widget/upload-widget.svelte b/apps/dashboard/src/lib/features/ui/upload-widget/upload-widget.svelte
index de2423af..eb5b113f 100644
--- a/apps/dashboard/src/lib/features/ui/upload-widget/upload-widget.svelte
+++ b/apps/dashboard/src/lib/features/ui/upload-widget/upload-widget.svelte
@@ -14,6 +14,7 @@
   import { InputField } from '@cio/ui/custom/input-field';
   import { Button } from '@cio/ui/base/button';
   import UploadCloudIcon from '@lucide/svelte/icons/upload-cloud';
+  import { getResolvedUploadLimits } from '$lib/utils/config/upload-limits-context';
 
   interface Props {
     imageURL?: string;
@@ -48,7 +49,8 @@
     alt_description: string;
   }[] = $state([]);
 
-  const MAX_IMAGE_SIZE = 500 * 1000;
+  const uploadLimits = getResolvedUploadLimits();
+  const maxLandingImageSize = uploadLimits.landingImageBytes;
 
   async function handleImageClick(img: string) {
     onchange?.(img);
@@ -58,7 +60,7 @@
   }
 
   function handleUnsupportedFile(file: File) {
-    if (file.size > MAX_IMAGE_SIZE) {
+    if (file.size > maxLandingImageSize) {
       snackbar.error('snackbar.landing_page_settings.error.file_size');
       return;
     }
@@ -130,7 +132,7 @@
               bind:src={cropperSrc}
               onCropped={handleCropped}
               onUnsupportedFile={handleUnsupportedFile}
-              maxFileSize={MAX_IMAGE_SIZE}
+              maxFileSize={maxLandingImageSize}
               accept=".jpg, .jpeg, .png, .webp"
               disabled={isUploading}
             >
diff --git a/apps/dashboard/src/lib/utils/config/upload-limits-context.ts b/apps/dashboard/src/lib/utils/config/upload-limits-context.ts
new file mode 100644
index 00000000..cff25887
--- /dev/null
+++ b/apps/dashboard/src/lib/utils/config/upload-limits-context.ts
@@ -0,0 +1,23 @@
+import { getContext, setContext } from 'svelte';
+import { resolveUploadLimits, type UploadLimits } from '@cio/utils/config/upload-limits';
+import type { UploadLimits as DashboardUploadLimits } from './upload-limits';
+
+const UPLOAD_LIMITS_CONTEXT_KEY = Symbol('upload-limits');
+
+export function setUploadLimitsContext(limits: DashboardUploadLimits) {
+  setContext(UPLOAD_LIMITS_CONTEXT_KEY, limits);
+}
+
+export function getUploadLimitsContext(): DashboardUploadLimits | null {
+  return getContext<DashboardUploadLimits | null>(UPLOAD_LIMITS_CONTEXT_KEY) ?? null;
+}
+
+/** Built-in defaults when layout context is absent (e.g. Storybook, isolated tests). */
+export function getDefaultUploadLimits(): UploadLimits {
+  return resolveUploadLimits({});
+}
+
+/** Layout-provided limits, or built-in defaults outside the dashboard layout tree. */
+export function getResolvedUploadLimits(): UploadLimits {
+  return getUploadLimitsContext() ?? getDefaultUploadLimits();
+}
diff --git a/apps/dashboard/src/lib/utils/config/upload-limits.ts b/apps/dashboard/src/lib/utils/config/upload-limits.ts
new file mode 100644
index 00000000..f39f540b
--- /dev/null
+++ b/apps/dashboard/src/lib/utils/config/upload-limits.ts
@@ -0,0 +1,24 @@
+import { resolveUploadLimits, type UploadLimits } from '@cio/utils/config/upload-limits';
+import { env } from '$env/dynamic/private';
+
+let cachedLimits: UploadLimits | null = null;
+
+export function getUploadLimits(): UploadLimits {
+  if (cachedLimits) {
+    return cachedLimits;
+  }
+
+  cachedLimits = resolveUploadLimits({
+    UPLOAD_MAX_DOCUMENT_MB: env.UPLOAD_MAX_DOCUMENT_MB,
+    UPLOAD_MAX_IMAGE_MB: env.UPLOAD_MAX_IMAGE_MB,
+    UPLOAD_MAX_VIDEO_MB: env.UPLOAD_MAX_VIDEO_MB,
+    UPLOAD_MAX_EXERCISE_FILE_MB: env.UPLOAD_MAX_EXERCISE_FILE_MB,
+    UPLOAD_MAX_AGENT_DOCUMENT_MB: env.UPLOAD_MAX_AGENT_DOCUMENT_MB,
+    UPLOAD_MAX_LANDING_IMAGE_MB: env.UPLOAD_MAX_LANDING_IMAGE_MB,
+    UPLOAD_MAX_THUMBNAIL_MB: env.UPLOAD_MAX_THUMBNAIL_MB
+  });
+
+  return cachedLimits;
+}
+
+export type { UploadLimits };
diff --git a/apps/dashboard/src/lib/utils/services/courses/presign.ts b/apps/dashboard/src/lib/utils/services/courses/presign.ts
index eccd1d41..c0a61bb7 100644
--- a/apps/dashboard/src/lib/utils/services/courses/presign.ts
+++ b/apps/dashboard/src/lib/utils/services/courses/presign.ts
@@ -52,8 +52,12 @@ export class GenericUploader {
   async getPresignedUrl(file: File) {
     const result =
       this.uploadType === 'document'
-        ? await presignApi.getDocumentUploadUrl(file?.name ?? '', file?.type ?? '')
-        : await presignApi.getVideoUploadUrl(file?.name ?? '', file?.type ?? '');
+        ? await presignApi.getDocumentUploadUrl(
+            file?.name ?? '',
+            file?.type ?? '',
+            file.size > 0 ? file.size : undefined
+          )
+        : await presignApi.getVideoUploadUrl(file?.name ?? '', file?.type ?? '', file.size > 0 ? file.size : undefined);
 
     if (!result) {
       throw new Error('Failed to get presigned upload URL');
diff --git a/apps/dashboard/src/routes/+layout.server.ts b/apps/dashboard/src/routes/+layout.server.ts
index 97db59a1..1d9e3882 100644
--- a/apps/dashboard/src/routes/+layout.server.ts
+++ b/apps/dashboard/src/routes/+layout.server.ts
@@ -1,8 +1,10 @@
 import type { AccountOrg } from '$features/app/types';
 import type { MetaTagsProps } from 'svelte-meta-tags';
+import type { UploadLimits } from '$lib/utils/config/upload-limits';
 import { PUBLIC_IS_SELFHOSTED } from '$env/static/public';
 import { getBaseMetaTags } from '$lib/utils/functions/metaTags';
 import { getOrgSiteInfo } from '$features/app/layout-setup';
+import { getUploadLimits } from '$lib/utils/config/upload-limits';
 
 export const ssr = true;
 
@@ -15,6 +17,7 @@ interface LoadOutput {
   serverLang: string;
   localeCookie: string;
   locals: App.Locals;
+  uploadLimits: UploadLimits;
 }
 
 export const load = async ({ url, cookies, request, locals }): Promise<LoadOutput> => {
@@ -33,7 +36,8 @@ export const load = async ({ url, cookies, request, locals }): Promise<LoadOutpu
     baseMetaTags: getBaseMetaTags(url, orgSiteInfo),
     serverLang: request.headers?.get('accept-language') || '',
     localeCookie: cookies.get('classroomio_locale') || '',
-    locals
+    locals,
+    uploadLimits: getUploadLimits()
   };
 
   const loadMs = Math.round((performance.now() - loadStart) * 100) / 100;
diff --git a/apps/dashboard/src/routes/+layout.svelte b/apps/dashboard/src/routes/+layout.svelte
index ff53bc98..44465f1b 100644
--- a/apps/dashboard/src/routes/+layout.svelte
+++ b/apps/dashboard/src/routes/+layout.svelte
@@ -16,8 +16,12 @@
 
   import '../app.css';
 
+  import { setUploadLimitsContext } from '$lib/utils/config/upload-limits-context';
+
   let { data, children } = $props();
 
+  setUploadLimitsContext(data.uploadLimits);
+
   const metaTags = $derived(merge(data.baseMetaTags, page.data.pageMetaTags));
 
   onMount(() => {
diff --git a/apps/docs/content/docs/self-hosted/coolify.mdx b/apps/docs/content/docs/self-hosted/coolify.mdx
index eccfdd63..907bb790 100644
--- a/apps/docs/content/docs/self-hosted/coolify.mdx
+++ b/apps/docs/content/docs/self-hosted/coolify.mdx
@@ -46,6 +46,9 @@ import { Callout } from 'fumadocs-ui/components/callout';
    storage instead? Point the same `OBJECT_STORAGE_*` variables at external **S3 / Cloudflare R2**
    and leave the `minio` profile off — see the [Cloudflare Setup](/docs/contributor-guides/cloudflare-setup) guide for R2.
 
+   **Upload size limits** (optional): set `UPLOAD_MAX_*_MB` in Coolify's env for both the `api` and
+   `dashboard` services (same values in each). See [Docker self-hosting → Upload file size limits](/docs/self-hosted/docker#optional--upload-file-size-limits).
+
 5. **Deploy.** Coolify pulls `classroomio/{api,dashboard,jobs}:${CIO_VERSION}`, starts Postgres + Redis, the API container runs database setup on first boot, then the dashboard and the **jobs worker** come up.
 
 ## Upgrades & rollback
diff --git a/apps/docs/content/docs/self-hosted/docker.mdx b/apps/docs/content/docs/self-hosted/docker.mdx
index 7a03c8b4..722585af 100644
--- a/apps/docs/content/docs/self-hosted/docker.mdx
+++ b/apps/docs/content/docs/self-hosted/docker.mdx
@@ -210,6 +210,25 @@ The bundled **MinIO** is included by default and the startup script auto-configu
 | `LICENSE_KEY` | Enterprise features (SSO, token-auth, no-tracking) |
 | `PUBLIC_APP_TITLE`, `PUBLIC_APP_DESCRIPTION`, `PUBLIC_OG_IMAGE_URL` | Custom branding |
 
+### Optional — Upload file size limits
+
+Set these in the root `.env` to raise or lower upload caps (values are in **megabytes**). Compose passes them through to the `api` and `dashboard` containers. Unset = built-in defaults. On [Railway](/docs/self-hosted/railway) or [Coolify](/docs/self-hosted/coolify), set the same variables on both the API and dashboard services.
+
+| Variable | Default | Applies to |
+|----------|---------|------------|
+| `UPLOAD_MAX_DOCUMENT_MB` | 5 | Course lesson documents |
+| `UPLOAD_MAX_IMAGE_MB` | 5 | Avatars, media library, editor images |
+| `UPLOAD_MAX_VIDEO_MB` | 800 | Lesson video uploads |
+| `UPLOAD_MAX_EXERCISE_FILE_MB` | 2 | Student assignment file-upload questions |
+| `UPLOAD_MAX_AGENT_DOCUMENT_MB` | 5 | AI assistant document uploads |
+| `UPLOAD_MAX_LANDING_IMAGE_MB` | 0.5 | Org landing page cover images |
+| `UPLOAD_MAX_THUMBNAIL_MB` | 5 | Media thumbnail uploads |
+
+<Callout type="warn" title="Reverse proxy limits">
+  If you raise these values, also increase your reverse proxy body-size limit (e.g. nginx
+  `client_max_body_size`) so large uploads are not rejected before they reach ClassroomIO.
+</Callout>
+
 ## Common Commands
 
 ```zsh title="Terminal"
diff --git a/apps/docs/content/docs/self-hosted/railway.mdx b/apps/docs/content/docs/self-hosted/railway.mdx
index 0db8dde8..36452101 100644
--- a/apps/docs/content/docs/self-hosted/railway.mdx
+++ b/apps/docs/content/docs/self-hosted/railway.mdx
@@ -62,6 +62,8 @@ ALLOWED_EXTERNAL_DOMAINS="https://fonts.googleapis.com"
 
 Optional: add `PUBLIC_APP_TITLE`, `PUBLIC_APP_DESCRIPTION`, `PUBLIC_OG_IMAGE_URL` for custom branding. You can also use per-directive CSP vars (`CSP_SCRIPT_SRC_DOMAINS`, `CSP_MEDIA_SRC_DOMAINS`, etc.) instead of `ALLOWED_EXTERNAL_DOMAINS` for finer control.
 
+**Upload size limits** (optional): add the same `UPLOAD_MAX_*_MB` values to **cio-api** and **cio-dashboard** (e.g. `UPLOAD_MAX_DOCUMENT_MB=50`). See [Docker self-hosting → Upload file size limits](/docs/self-hosted/docker#optional--upload-file-size-limits).
+
 ## cio-jobs (background worker)
 
 The jobs worker has **no public domain** — it drains the Redis queue (video processing, transcription, AI course generation, and emails). It shares the same Postgres, Redis, storage, email, and OpenAI settings as the API:
diff --git a/docker-compose.images.yaml b/docker-compose.images.yaml
index ff884f65..cdbe9c51 100644
--- a/docker-compose.images.yaml
+++ b/docker-compose.images.yaml
@@ -28,8 +28,8 @@ services:
       # (pg_isready can pass while DB is still in recovery, causing 57P03 on sign-in)
       test:
         [
-          "CMD-SHELL",
-          "pg_isready -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-classroomio} && psql -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-classroomio} -tAc 'SELECT 1'",
+          'CMD-SHELL',
+          "pg_isready -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-classroomio} && psql -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-classroomio} -tAc 'SELECT 1'"
         ]
       interval: 5s
       timeout: 5s
@@ -39,11 +39,11 @@ services:
   redis:
     image: redis:7-alpine
     container_name: cio-redis
-    command: ["redis-server", "--appendonly", "yes"]
+    command: ['redis-server', '--appendonly', 'yes']
     volumes:
       - redis-data:/data
     healthcheck:
-      test: ["CMD", "redis-cli", "ping"]
+      test: ['CMD', 'redis-cli', 'ping']
       interval: 5s
       timeout: 3s
       retries: 10
@@ -54,8 +54,8 @@ services:
     container_name: cio-minio
     command: server /data --console-address ":9001"
     ports:
-      - "9000:9000"
-      - "9001:9001"
+      - '9000:9000'
+      - '9001:9001'
     environment:
       MINIO_ROOT_USER: ${MINIO_ROOT_USER:-minioadmin}
       MINIO_ROOT_PASSWORD: ${MINIO_ROOT_PASSWORD:-minioadmin}
@@ -91,7 +91,7 @@ services:
     image: classroomio/api:${CIO_VERSION:-latest}
     container_name: cio-api
     ports:
-      - "3081:3081"
+      - '3081:3081'
     depends_on:
       postgres:
         condition: service_healthy
@@ -101,10 +101,10 @@ services:
       # node:slim has no curl/wget; use Node's global fetch (Node 20+).
       test:
         [
-          "CMD",
-          "node",
-          "-e",
-          "fetch('http://localhost:3081/').then(r=>process.exit(r.ok?0:1)).catch(()=>process.exit(1))",
+          'CMD',
+          'node',
+          '-e',
+          "fetch('http://localhost:3081/').then(r=>process.exit(r.ok?0:1)).catch(()=>process.exit(1))"
         ]
       interval: 10s
       timeout: 5s
@@ -138,6 +138,12 @@ services:
       DASHBOARD_ORIGIN: ${DASHBOARD_ORIGIN:-}
       LICENSE_KEY: ${LICENSE_KEY:-}
       UNSPLASH_API_KEY: ${UNSPLASH_API_KEY:-}
+      # Upload size limits (megabytes). Unset = built-in defaults — see .env.example.
+      UPLOAD_MAX_DOCUMENT_MB: ${UPLOAD_MAX_DOCUMENT_MB:-}
+      UPLOAD_MAX_IMAGE_MB: ${UPLOAD_MAX_IMAGE_MB:-}
+      UPLOAD_MAX_VIDEO_MB: ${UPLOAD_MAX_VIDEO_MB:-}
+      UPLOAD_MAX_EXERCISE_FILE_MB: ${UPLOAD_MAX_EXERCISE_FILE_MB:-}
+      UPLOAD_MAX_AGENT_DOCUMENT_MB: ${UPLOAD_MAX_AGENT_DOCUMENT_MB:-}
       BETTER_AUTH_SECRET: ${BETTER_AUTH_SECRET:?set a strong BETTER_AUTH_SECRET in .env}
       SKIP_DB_SETUP: ${SKIP_DB_SETUP:-}
     restart: unless-stopped
@@ -146,7 +152,7 @@ services:
     image: classroomio/dashboard:${CIO_VERSION:-latest}
     container_name: cio-dashboard
     ports:
-      - "3082:3082"
+      - '3082:3082'
     depends_on:
       api:
         condition: service_healthy
@@ -166,6 +172,14 @@ services:
       CSP_FRAME_SRC_DOMAINS: ${CSP_FRAME_SRC_DOMAINS:-}
       CSP_FONT_SRC_DOMAINS: ${CSP_FONT_SRC_DOMAINS:-}
       CSP_MEDIA_SRC_DOMAINS: ${CSP_MEDIA_SRC_DOMAINS:-}
+      # Upload size limits (megabytes). Unset = built-in defaults — see .env.example.
+      UPLOAD_MAX_DOCUMENT_MB: ${UPLOAD_MAX_DOCUMENT_MB:-}
+      UPLOAD_MAX_IMAGE_MB: ${UPLOAD_MAX_IMAGE_MB:-}
+      UPLOAD_MAX_VIDEO_MB: ${UPLOAD_MAX_VIDEO_MB:-}
+      UPLOAD_MAX_EXERCISE_FILE_MB: ${UPLOAD_MAX_EXERCISE_FILE_MB:-}
+      UPLOAD_MAX_AGENT_DOCUMENT_MB: ${UPLOAD_MAX_AGENT_DOCUMENT_MB:-}
+      UPLOAD_MAX_LANDING_IMAGE_MB: ${UPLOAD_MAX_LANDING_IMAGE_MB:-}
+      UPLOAD_MAX_THUMBNAIL_MB: ${UPLOAD_MAX_THUMBNAIL_MB:-}
     restart: unless-stopped
 
   # Background worker (BullMQ). Drains the Redis queue: video processing, transcription,
diff --git a/docker-compose.yaml b/docker-compose.yaml
index 39fa6a94..d0888f2b 100644
--- a/docker-compose.yaml
+++ b/docker-compose.yaml
@@ -5,7 +5,7 @@ services:
     # Bound to localhost only so host tools (pnpm api:dev, db:setup) can reach it
     # without exposing the database to the LAN.
     ports:
-      - "127.0.0.1:5432:5432"
+      - '127.0.0.1:5432:5432'
     environment:
       POSTGRES_DB: ${POSTGRES_DB:-classroomio}
       POSTGRES_USER: ${POSTGRES_USER:-postgres}
@@ -17,8 +17,8 @@ services:
       # (pg_isready can pass while DB is still in recovery, causing 57P03 on sign-in)
       test:
         [
-          "CMD-SHELL",
-          "pg_isready -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-classroomio} && psql -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-classroomio} -tAc 'SELECT 1'",
+          'CMD-SHELL',
+          "pg_isready -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-classroomio} && psql -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-classroomio} -tAc 'SELECT 1'"
         ]
       interval: 5s
       timeout: 5s
@@ -30,12 +30,12 @@ services:
     container_name: cio-redis
     # Bound to localhost only (see postgres note above).
     ports:
-      - "127.0.0.1:6379:6379"
-    command: ["redis-server", "--appendonly", "yes"]
+      - '127.0.0.1:6379:6379'
+    command: ['redis-server', '--appendonly', 'yes']
     volumes:
       - redis-data:/data
     healthcheck:
-      test: ["CMD", "redis-cli", "ping"]
+      test: ['CMD', 'redis-cli', 'ping']
       interval: 5s
       timeout: 3s
       retries: 10
@@ -46,8 +46,8 @@ services:
     container_name: cio-minio
     command: server /data --console-address ":9001"
     ports:
-      - "9000:9000"
-      - "9001:9001"
+      - '9000:9000'
+      - '9001:9001'
     environment:
       MINIO_ROOT_USER: ${MINIO_ROOT_USER:-minioadmin}
       MINIO_ROOT_PASSWORD: ${MINIO_ROOT_PASSWORD:-minioadmin}
@@ -85,7 +85,7 @@ services:
       dockerfile: docker/Dockerfile.api
     container_name: cio-api
     ports:
-      - "3081:3081"
+      - '3081:3081'
     depends_on:
       postgres:
         condition: service_healthy
@@ -95,10 +95,10 @@ services:
       # node:slim has no curl/wget; use Node's global fetch (Node 20+).
       test:
         [
-          "CMD",
-          "node",
-          "-e",
-          "fetch('http://localhost:3081/').then(r=>process.exit(r.ok?0:1)).catch(()=>process.exit(1))",
+          'CMD',
+          'node',
+          '-e',
+          "fetch('http://localhost:3081/').then(r=>process.exit(r.ok?0:1)).catch(()=>process.exit(1))"
         ]
       interval: 10s
       timeout: 5s
@@ -132,6 +132,12 @@ services:
       DASHBOARD_ORIGIN: ${DASHBOARD_ORIGIN:-}
       LICENSE_KEY: ${LICENSE_KEY:-}
       UNSPLASH_API_KEY: ${UNSPLASH_API_KEY:-}
+      # Upload size limits (megabytes). Unset = built-in defaults — see .env.example.
+      UPLOAD_MAX_DOCUMENT_MB: ${UPLOAD_MAX_DOCUMENT_MB:-}
+      UPLOAD_MAX_IMAGE_MB: ${UPLOAD_MAX_IMAGE_MB:-}
+      UPLOAD_MAX_VIDEO_MB: ${UPLOAD_MAX_VIDEO_MB:-}
+      UPLOAD_MAX_EXERCISE_FILE_MB: ${UPLOAD_MAX_EXERCISE_FILE_MB:-}
+      UPLOAD_MAX_AGENT_DOCUMENT_MB: ${UPLOAD_MAX_AGENT_DOCUMENT_MB:-}
       BETTER_AUTH_SECRET: ${BETTER_AUTH_SECRET:?set a strong BETTER_AUTH_SECRET in .env}
       SKIP_DB_SETUP: ${SKIP_DB_SETUP:-}
     restart: unless-stopped
@@ -144,7 +150,7 @@ services:
         PUBLIC_IS_SELFHOSTED: ${PUBLIC_IS_SELFHOSTED:-true}
     container_name: cio-dashboard
     ports:
-      - "3082:3082"
+      - '3082:3082'
     depends_on:
       api:
         condition: service_healthy
@@ -164,6 +170,14 @@ services:
       CSP_FRAME_SRC_DOMAINS: ${CSP_FRAME_SRC_DOMAINS:-}
       CSP_FONT_SRC_DOMAINS: ${CSP_FONT_SRC_DOMAINS:-}
       CSP_MEDIA_SRC_DOMAINS: ${CSP_MEDIA_SRC_DOMAINS:-}
+      # Upload size limits (megabytes). Unset = built-in defaults — see .env.example.
+      UPLOAD_MAX_DOCUMENT_MB: ${UPLOAD_MAX_DOCUMENT_MB:-}
+      UPLOAD_MAX_IMAGE_MB: ${UPLOAD_MAX_IMAGE_MB:-}
+      UPLOAD_MAX_VIDEO_MB: ${UPLOAD_MAX_VIDEO_MB:-}
+      UPLOAD_MAX_EXERCISE_FILE_MB: ${UPLOAD_MAX_EXERCISE_FILE_MB:-}
+      UPLOAD_MAX_AGENT_DOCUMENT_MB: ${UPLOAD_MAX_AGENT_DOCUMENT_MB:-}
+      UPLOAD_MAX_LANDING_IMAGE_MB: ${UPLOAD_MAX_LANDING_IMAGE_MB:-}
+      UPLOAD_MAX_THUMBNAIL_MB: ${UPLOAD_MAX_THUMBNAIL_MB:-}
     restart: unless-stopped
 
   # Background worker (BullMQ). Drains the Redis queue: video processing, transcription,
diff --git a/docker/docs/SELF_HOST.md b/docker/docs/SELF_HOST.md
index 6bec0455..4928e127 100644
--- a/docker/docs/SELF_HOST.md
+++ b/docker/docs/SELF_HOST.md
@@ -88,6 +88,7 @@ Key points:
 - **Auto-configured:** All `MINIO_*` / `OBJECT_STORAGE_*` vars (by the startup script, with randomized MinIO credentials).
 - **Email (effectively required):** SMTP (or Zoho). See [Email](#email) — without it, signup verification, password reset, and invites do not send.
 - **Optional:** Google OAuth, Unsplash, `LICENSE_KEY` (enterprise).
+- **Optional — upload limits:** `UPLOAD_MAX_*_MB` vars (documents, images, videos, assignment files, etc.). See [`.env.example`](../../.env.example). Passed through to both `api` and `dashboard` containers; unset values use built-in defaults. Raise your reverse-proxy body-size limit too if you increase these.
 
 `PRIVATE_SERVER_KEY` must be the same value in both API and dashboard — the script ensures this.
 
diff --git a/packages/core/src/config/env.ts b/packages/core/src/config/env.ts
index 61bfa7b8..30ae0281 100644
--- a/packages/core/src/config/env.ts
+++ b/packages/core/src/config/env.ts
@@ -88,7 +88,21 @@ const envSchema = z.object({
       const parsed = Number(v);
 
       return Number.isFinite(parsed) && parsed >= 1 ? Math.trunc(parsed) : 500;
-    })
+    }),
+  /** Max course lesson document upload size in megabytes (default 5). */
+  UPLOAD_MAX_DOCUMENT_MB: z.string().optional(),
+  /** Max image upload size in megabytes — avatars, media, editor images (default 5). */
+  UPLOAD_MAX_IMAGE_MB: z.string().optional(),
+  /** Max lesson video upload size in megabytes (default 800). */
+  UPLOAD_MAX_VIDEO_MB: z.string().optional(),
+  /** Max exercise assignment file upload size in megabytes (default 2). */
+  UPLOAD_MAX_EXERCISE_FILE_MB: z.string().optional(),
+  /** Max AI assistant document upload size in megabytes (default 5). */
+  UPLOAD_MAX_AGENT_DOCUMENT_MB: z.string().optional(),
+  /** Max org landing page image upload size in megabytes (default 0.5). */
+  UPLOAD_MAX_LANDING_IMAGE_MB: z.string().optional(),
+  /** Max media thumbnail upload size in megabytes (default 5). */
+  UPLOAD_MAX_THUMBNAIL_MB: z.string().optional()
 });
 
 export const env = envSchema.parse(process.env);
diff --git a/packages/core/src/config/upload-limits.ts b/packages/core/src/config/upload-limits.ts
new file mode 100644
index 00000000..62ada419
--- /dev/null
+++ b/packages/core/src/config/upload-limits.ts
@@ -0,0 +1,15 @@
+import { env } from './env';
+import { resolveUploadLimits, type UploadLimits } from '@cio/utils/config/upload-limits';
+
+export type { UploadLimits } from '@cio/utils/config/upload-limits';
+
+let cachedLimits: UploadLimits | null = null;
+
+export function getUploadLimits(): UploadLimits {
+  if (cachedLimits) {
+    return cachedLimits;
+  }
+
+  cachedLimits = resolveUploadLimits(env);
+  return cachedLimits;
+}
diff --git a/packages/core/src/services/agent/document.ts b/packages/core/src/services/agent/document.ts
index ca66c029..7dd0066d 100644
--- a/packages/core/src/services/agent/document.ts
+++ b/packages/core/src/services/agent/document.ts
@@ -1,12 +1,8 @@
 import { nanoid } from 'nanoid';
 import { AppError } from '@cio/utils/errors';
-import {
-  MAX_DOCUMENT_TEXT_LENGTH,
-  MAX_AGENT_DOCUMENT_SIZE,
-  DOCUMENT_REDIS_TTL,
-  SUPPORTED_DOCUMENT_TYPES
-} from '@cio/ai-assistant';
+import { MAX_DOCUMENT_TEXT_LENGTH, DOCUMENT_REDIS_TTL, SUPPORTED_DOCUMENT_TYPES } from '@cio/ai-assistant';
 import type { DocumentUploadResult } from '@cio/ai-assistant';
+import { getUploadLimits } from '../../config/upload-limits';
 import { agentDocumentKey } from '../../utils/redis-keys';
 import { trackAgentEvent, AgentEvent } from '../../utils/tinybird';
 import type { RedisClient } from '../../utils/redis/redis';
@@ -34,9 +30,11 @@ export async function parseAndStoreDocument(
     throw new AppError('Unsupported file type. Allowed: PDF, DOCX, PPTX', 'UNSUPPORTED_FILE_TYPE', 415);
   }
 
-  if (file.size > MAX_AGENT_DOCUMENT_SIZE) {
+  const maxAgentDocumentSize = getUploadLimits().agentDocumentBytes;
+
+  if (file.size > maxAgentDocumentSize) {
     throw new AppError(
-      `File too large. Maximum size is ${MAX_AGENT_DOCUMENT_SIZE / (1024 * 1024)}MB`,
+      `File too large. Maximum size is ${maxAgentDocumentSize / (1024 * 1024)}MB`,
       'FILE_TOO_LARGE',
       413
     );
diff --git a/packages/question-types/src/exercise-types.ts b/packages/question-types/src/exercise-types.ts
index ce00405e..b368d3ab 100644
--- a/packages/question-types/src/exercise-types.ts
+++ b/packages/question-types/src/exercise-types.ts
@@ -257,6 +257,8 @@ export interface ExerciseQuestionRendererProps {
   maxSubmissionItems?: number;
   disabled?: boolean;
   labels?: ExerciseQuestionLabels;
+  /** Platform-wide cap for exercise file uploads (megabytes). */
+  platformMaxFileSizeMb?: number;
   onAnswerChange?: (answer: AnswerData | null) => void;
   onQuestionChange?: (question: ExerciseQuestionModel) => void;
   onImageUpload?: ExerciseQuestionImageUploader;
diff --git a/packages/question-types/src/render-contract.ts b/packages/question-types/src/render-contract.ts
index e947ff3a..d8142f5d 100644
--- a/packages/question-types/src/render-contract.ts
+++ b/packages/question-types/src/render-contract.ts
@@ -18,6 +18,8 @@ export interface ExerciseQuestionRenderContract {
   maxSubmissionItems?: number;
   disabled?: boolean;
   labels?: ExerciseQuestionLabels;
+  /** Platform-wide cap for exercise file uploads (megabytes). */
+  platformMaxFileSizeMb?: number;
   onImageUpload?: ExerciseQuestionImageUploader;
   onFileUpload?: ExerciseQuestionFileUploader;
   onVideoRecordingUpload?: ExerciseQuestionVideoRecordingUploader;
@@ -31,6 +33,8 @@ export interface ExerciseQuestionListRenderContract {
   maxSubmissionItems?: number;
   disabled?: boolean;
   labels?: ExerciseQuestionLabels;
+  /** Platform-wide cap for exercise file uploads (megabytes). */
+  platformMaxFileSizeMb?: number;
   onImageUpload?: ExerciseQuestionImageUploader;
   onFileUpload?: ExerciseQuestionFileUploader;
   onVideoRecordingUpload?: ExerciseQuestionVideoRecordingUploader;
diff --git a/packages/ui/src/custom/exercise-question/question-list.svelte b/packages/ui/src/custom/exercise-question/question-list.svelte
index d86b44f0..6a5fb0d1 100644
--- a/packages/ui/src/custom/exercise-question/question-list.svelte
+++ b/packages/ui/src/custom/exercise-question/question-list.svelte
@@ -32,6 +32,7 @@
         maxSubmissionItems: contract.maxSubmissionItems,
         disabled: contract.disabled,
         labels: contract.labels,
+        platformMaxFileSizeMb: contract.platformMaxFileSizeMb,
         onImageUpload: contract.onImageUpload,
         onFileUpload: contract.onFileUpload,
         onVideoRecordingUpload: contract.onVideoRecordingUpload
diff --git a/packages/ui/src/custom/exercise-question/question-renderer.svelte b/packages/ui/src/custom/exercise-question/question-renderer.svelte
index d722a589..9fc04ff0 100644
--- a/packages/ui/src/custom/exercise-question/question-renderer.svelte
+++ b/packages/ui/src/custom/exercise-question/question-renderer.svelte
@@ -475,6 +475,7 @@
     maxSubmissionItems={contract.maxSubmissionItems}
     disabled={contract.disabled}
     labels={contract.labels}
+    platformMaxFileSizeMb={contract.platformMaxFileSizeMb}
     onImageUpload={contract.onImageUpload}
     onFileUpload={contract.onFileUpload}
     onVideoRecordingUpload={contract.onVideoRecordingUpload}
diff --git a/packages/ui/src/custom/exercise-question/renderers/file-upload-types.ts b/packages/ui/src/custom/exercise-question/renderers/file-upload-types.ts
index 17d68926..2fbbd413 100644
--- a/packages/ui/src/custom/exercise-question/renderers/file-upload-types.ts
+++ b/packages/ui/src/custom/exercise-question/renderers/file-upload-types.ts
@@ -1,4 +1,6 @@
-export const FILE_UPLOAD_MAX_SIZE_MB = 2;
+export const FILE_UPLOAD_DEFAULT_MAX_SIZE_MB = 2;
+/** @deprecated Use FILE_UPLOAD_DEFAULT_MAX_SIZE_MB */
+export const FILE_UPLOAD_MAX_SIZE_MB = FILE_UPLOAD_DEFAULT_MAX_SIZE_MB;
 
 export const FILE_UPLOAD_SUPPORTED_TYPES = [
   { value: 'application/pdf', label: 'PDF (.pdf)', aliases: ['pdf', '.pdf'] },
@@ -106,10 +108,25 @@ export function isFileTypeAllowed(file: File, acceptedTypes: string[]): boolean
 
 const BYTES_PER_MB = 1024 * 1024;
 
-export function isFileSizeAllowed(file: File, maxSizeMb: number | undefined | null): boolean {
-  const effectiveMaxMb = Math.min(
-    typeof maxSizeMb === 'number' && maxSizeMb > 0 ? maxSizeMb : FILE_UPLOAD_MAX_SIZE_MB,
-    FILE_UPLOAD_MAX_SIZE_MB
-  );
+export function resolveExerciseFileUploadMaxSizeMb(
+  questionMaxSizeMb: number | undefined | null,
+  platformMaxSizeMb: number = FILE_UPLOAD_DEFAULT_MAX_SIZE_MB
+): number {
+  const effectivePlatformMax =
+    typeof platformMaxSizeMb === 'number' && platformMaxSizeMb > 0
+      ? platformMaxSizeMb
+      : FILE_UPLOAD_DEFAULT_MAX_SIZE_MB;
+  const requestedMax =
+    typeof questionMaxSizeMb === 'number' && questionMaxSizeMb > 0 ? questionMaxSizeMb : effectivePlatformMax;
+
+  return Math.min(requestedMax, effectivePlatformMax);
+}
+
+export function isFileSizeAllowed(
+  file: File,
+  maxSizeMb: number | undefined | null,
+  platformMaxSizeMb: number = FILE_UPLOAD_DEFAULT_MAX_SIZE_MB
+): boolean {
+  const effectiveMaxMb = resolveExerciseFileUploadMaxSizeMb(maxSizeMb, platformMaxSizeMb);
   return file.size <= effectiveMaxMb * BYTES_PER_MB;
 }
diff --git a/packages/ui/src/custom/exercise-question/renderers/file-upload/edit.svelte b/packages/ui/src/custom/exercise-question/renderers/file-upload/edit.svelte
index eeb0e22d..f93bca8a 100644
--- a/packages/ui/src/custom/exercise-question/renderers/file-upload/edit.svelte
+++ b/packages/ui/src/custom/exercise-question/renderers/file-upload/edit.svelte
@@ -12,10 +12,17 @@
   import {
     FILE_UPLOAD_SUPPORTED_TYPES,
     formatAcceptedFileTypes,
-    normalizeAcceptedFileTypes
+    normalizeAcceptedFileTypes,
+    resolveExerciseFileUploadMaxSizeMb
   } from '../file-upload-types';
 
-  let { question, disabled = false, labels, onQuestionChange = () => {} }: ExerciseQuestionRendererProps = $props();
+  let {
+    question,
+    disabled = false,
+    labels,
+    platformMaxFileSizeMb,
+    onQuestionChange = () => {}
+  }: ExerciseQuestionRendererProps = $props();
   const label = (key: Parameters<typeof getExerciseQuestionLabel>[1], fallback = '') =>
     getExerciseQuestionLabel(labels, key, fallback);
   const acceptedTypes = $derived(normalizeAcceptedFileTypes(question.settings?.acceptedTypes));
@@ -41,17 +48,19 @@
     patchSettings({ acceptedTypes: nextAcceptedTypes });
   }
 
+  const platformMaxMb = $derived(resolveExerciseFileUploadMaxSizeMb(undefined, platformMaxFileSizeMb));
+
   const rawMaxSize = $derived(question.settings?.maxSizeMb as number | undefined);
   const maxSizeMb = $derived(
     typeof rawMaxSize === 'number' && !Number.isNaN(rawMaxSize) && rawMaxSize >= 0
-      ? String(Math.min(rawMaxSize, 2))
+      ? String(Math.min(rawMaxSize, platformMaxMb))
       : ''
   );
 
   $effect(() => {
     const raw = question.settings?.maxSizeMb as number | undefined;
-    if (typeof raw === 'number' && raw > 2) {
-      patchSettings({ maxSizeMb: 2 });
+    if (typeof raw === 'number' && raw > platformMaxMb) {
+      patchSettings({ maxSizeMb: platformMaxMb });
     }
   });
 
@@ -61,7 +70,7 @@
       patchSettings({ maxSizeMb: undefined });
       return;
     }
-    patchSettings({ maxSizeMb: Math.min(2, Math.max(0, num)) });
+    patchSettings({ maxSizeMb: Math.min(platformMaxMb, Math.max(0, num)) });
   }
 </script>
 
@@ -107,7 +116,7 @@
       <Input
         type="number"
         min="0"
-        max="2"
+        max={platformMaxMb}
         step="0.1"
         placeholder={label('file_upload.edit.max_size_placeholder')}
         value={maxSizeMb}
diff --git a/packages/ui/src/custom/exercise-question/renderers/file-upload/take.svelte b/packages/ui/src/custom/exercise-question/renderers/file-upload/take.svelte
index bad4e72f..8e09f163 100644
--- a/packages/ui/src/custom/exercise-question/renderers/file-upload/take.svelte
+++ b/packages/ui/src/custom/exercise-question/renderers/file-upload/take.svelte
@@ -11,6 +11,7 @@
     answer = null,
     disabled = false,
     labels,
+    platformMaxFileSizeMb,
     onAnswerChange = () => {},
     onFileUpload
   }: ExerciseQuestionRendererProps = $props();
@@ -86,7 +87,7 @@
 
     if (!selectedFile) return;
     if (!isFileTypeAllowed(selectedFile, acceptedTypes)) return;
-    if (!isFileSizeAllowed(selectedFile, maxSizeMb)) return;
+    if (!isFileSizeAllowed(selectedFile, maxSizeMb, platformMaxFileSizeMb)) return;
 
     if (!onFileUpload) return;
 
diff --git a/packages/utils/package.json b/packages/utils/package.json
index 55a374f8..34eb53bc 100644
--- a/packages/utils/package.json
+++ b/packages/utils/package.json
@@ -52,6 +52,10 @@
     "./errors": {
       "types": "./dist/errors/index.d.ts",
       "default": "./dist/errors/index.js"
+    },
+    "./config/upload-limits": {
+      "types": "./dist/config/upload-limits.d.ts",
+      "default": "./dist/config/upload-limits.js"
     }
   },
   "scripts": {
diff --git a/packages/utils/src/config/upload-limits.ts b/packages/utils/src/config/upload-limits.ts
new file mode 100644
index 00000000..73ffd7bc
--- /dev/null
+++ b/packages/utils/src/config/upload-limits.ts
@@ -0,0 +1,69 @@
+const BYTES_PER_MB = 1024 * 1024;
+
+function parseUploadLimitMb(value: string | undefined, defaultMb: number): number {
+  if (value === undefined || value === '') {
+    return defaultMb;
+  }
+
+  const parsed = Number(value);
+
+  if (!Number.isFinite(parsed) || parsed <= 0) {
+    return defaultMb;
+  }
+
+  return parsed;
+}
+
+export type UploadLimits = {
+  documentMb: number;
+  imageMb: number;
+  videoMb: number;
+  exerciseFileMb: number;
+  agentDocumentMb: number;
+  landingImageMb: number;
+  thumbnailMb: number;
+  documentBytes: number;
+  imageBytes: number;
+  videoBytes: number;
+  exerciseFileBytes: number;
+  agentDocumentBytes: number;
+  landingImageBytes: number;
+  thumbnailBytes: number;
+};
+
+export type UploadLimitEnv = {
+  UPLOAD_MAX_DOCUMENT_MB?: string;
+  UPLOAD_MAX_IMAGE_MB?: string;
+  UPLOAD_MAX_VIDEO_MB?: string;
+  UPLOAD_MAX_EXERCISE_FILE_MB?: string;
+  UPLOAD_MAX_AGENT_DOCUMENT_MB?: string;
+  UPLOAD_MAX_LANDING_IMAGE_MB?: string;
+  UPLOAD_MAX_THUMBNAIL_MB?: string;
+};
+
+export function resolveUploadLimits(env: UploadLimitEnv): UploadLimits {
+  const documentMb = parseUploadLimitMb(env.UPLOAD_MAX_DOCUMENT_MB, 5);
+  const imageMb = parseUploadLimitMb(env.UPLOAD_MAX_IMAGE_MB, 5);
+  const videoMb = parseUploadLimitMb(env.UPLOAD_MAX_VIDEO_MB, 800);
+  const exerciseFileMb = parseUploadLimitMb(env.UPLOAD_MAX_EXERCISE_FILE_MB, 2);
+  const agentDocumentMb = parseUploadLimitMb(env.UPLOAD_MAX_AGENT_DOCUMENT_MB, 5);
+  const landingImageMb = parseUploadLimitMb(env.UPLOAD_MAX_LANDING_IMAGE_MB, 0.5);
+  const thumbnailMb = parseUploadLimitMb(env.UPLOAD_MAX_THUMBNAIL_MB, 5);
+
+  return {
+    documentMb,
+    imageMb,
+    videoMb,
+    exerciseFileMb,
+    agentDocumentMb,
+    landingImageMb,
+    thumbnailMb,
+    documentBytes: documentMb * BYTES_PER_MB,
+    imageBytes: imageMb * BYTES_PER_MB,
+    videoBytes: videoMb * BYTES_PER_MB,
+    exerciseFileBytes: exerciseFileMb * BYTES_PER_MB,
+    agentDocumentBytes: agentDocumentMb * BYTES_PER_MB,
+    landingImageBytes: landingImageMb * BYTES_PER_MB,
+    thumbnailBytes: thumbnailMb * BYTES_PER_MB
+  };
+}
diff --git a/packages/utils/src/validation/course/course.ts b/packages/utils/src/validation/course/course.ts
index 60554c2a..110e5506 100644
--- a/packages/utils/src/validation/course/course.ts
+++ b/packages/utils/src/validation/course/course.ts
@@ -127,13 +127,15 @@ export type TLessonDownloadContent = z.infer<typeof ZLessonDownloadContent>;
 
 export const ZCoursePresignUrlUpload = z.object({
   fileName: z.string().min(1),
-  fileType: z.enum(ALLOWED_CONTENT_TYPES)
+  fileType: z.enum(ALLOWED_CONTENT_TYPES),
+  fileSize: z.number().int().min(0).optional()
 });
 export type TCoursePresignUrlUpload = z.infer<typeof ZCoursePresignUrlUpload>;
 
 export const ZCourseDocumentPresignUrlUpload = z.object({
   fileName: z.string().min(1),
-  fileType: z.enum(ALLOWED_DOCUMENT_TYPES)
+  fileType: z.enum(ALLOWED_DOCUMENT_TYPES),
+  fileSize: z.number().int().min(0).optional()
 });
 export type TCourseDocumentPresignUrlUpload = z.infer<typeof ZCourseDocumentPresignUrlUpload>;