diff --git a/src/app/components/upload-card/UploadCardRenderer.tsx b/src/app/components/upload-card/UploadCardRenderer.tsx
index ad720e5b6..e17b656a4 100644
--- a/src/app/components/upload-card/UploadCardRenderer.tsx
+++ b/src/app/components/upload-card/UploadCardRenderer.tsx
@@ -104,7 +104,7 @@ type CompressionCheckboxProps = {
   setMetadata: (fileItem: TUploadItem, metadata: TUploadMetadata) => void;
 };
 function CompressionCheckbox({ fileItem, metadata, setMetadata }: CompressionCheckboxProps) {
-  const originalFile = fileItem.originalFile as File;
+  const originalFile = fileItem.originalFile as File | Blob;
   const [compressing, setCompressing] = useState(false);
   const compressPromiseRef = useRef<Promise<void> | null>(null);
 
@@ -136,6 +136,7 @@ function CompressionCheckbox({ fileItem, metadata, setMetadata }: CompressionChe
       : null;
 
   const originalSize = formatFileSize(originalFile.size);
+  const fileId = `compress-${(originalFile as File).name ?? ''}-${originalFile.size}`;
 
   return (
     <Box
@@ -152,14 +153,14 @@ function CompressionCheckbox({ fileItem, metadata, setMetadata }: CompressionChe
       {/* Checkbox row */}
       <Box alignItems="Center" gap="200">
         <input
-          id={`compress-${originalFile.name}-${originalFile.size}`}
+          id={fileId}
           type="checkbox"
           checked={checked}
           onChange={handleChange}
           style={{ cursor: 'pointer', flexShrink: 0 }}
         />
         <label
-          htmlFor={`compress-${originalFile.name}-${originalFile.size}`}
+          htmlFor={fileId}
           style={{
             cursor: 'pointer',
             color: color.SurfaceVariant.OnContainer,
diff --git a/src/app/features/room/RoomInput.tsx b/src/app/features/room/RoomInput.tsx
index 0444365f2..d838ede22 100644
--- a/src/app/features/room/RoomInput.tsx
+++ b/src/app/features/room/RoomInput.tsx
@@ -67,7 +67,7 @@ import {
   mxcUrlToHttp,
   tryDeleteMxcContent,
 } from '../../utils/matrix';
-import { compressImage } from '../../utils/imageCompression';
+import { compressImage, isCompressible } from '../../utils/imageCompression';
 import { useTypingStatusUpdater } from '../../hooks/useTypingStatusUpdater';
 import { useFilePicker } from '../../hooks/useFilePicker';
 import { useFilePasteHandler } from '../../hooks/useFilePasteHandler';
@@ -412,16 +412,11 @@ export const RoomInput = forwardRef<HTMLDivElement, RoomInputProps>(
         // Resolve the MXC URL to use — may be overridden if compression is enabled
         let mxc = upload.mxc;
 
-        if (
-          fileItem.metadata.compressImage &&
-          fileItem.originalFile.type.startsWith('image') &&
-          (fileItem.originalFile.type === 'image/jpeg' ||
-            fileItem.originalFile.type === 'image/png')
-        ) {
+        if (fileItem.metadata.compressImage && isCompressible(fileItem.originalFile)) {
           // Use the cached compression result if available, otherwise compute it now
           let compressionResult = fileItem.metadata.compressionResult;
           if (compressionResult === undefined) {
-            compressionResult = await compressImage(fileItem.originalFile as File);
+            compressionResult = await compressImage(fileItem.originalFile);
           }
 
           if (compressionResult) {
diff --git a/src/app/utils/imageCompression.ts b/src/app/utils/imageCompression.ts
index 757a45eaa..35cc6e95a 100644
--- a/src/app/utils/imageCompression.ts
+++ b/src/app/utils/imageCompression.ts
@@ -6,19 +6,26 @@ export type CompressionResult = {
   height: number;
 };
 
-const COMPRESSIBLE_TYPES = ['image/jpeg', 'image/png'];
+// Any raster image the browser can render to canvas can be compressed to JPEG.
+// SVG is vector and must stay as-is; GIF animation is lost on canvas but static
+// frames compress fine. Empty type string (undetected MIME) is excluded.
+const isCompressibleType = (type: string): boolean =>
+  type.startsWith('image/') && type !== 'image/svg+xml' && type !== '';
 
-/** Returns true if this file type can be compressed (JPEG or PNG, any size). */
-export function isCompressible(file: File): boolean {
-  return COMPRESSIBLE_TYPES.includes(file.type);
+/** Returns true if this file can be compressed via canvas (any raster image type). */
+export function isCompressible(file: File | Blob): boolean {
+  return isCompressibleType(file.type);
 }
 
 /**
- * Compress an image file via canvas.toBlob.
- * Returns null if the file type is not compressible (GIF, SVG, WebP, video, audio, etc.).
+ * Compress an image file via canvas.toBlob → JPEG at the given quality.
+ * Returns null if the browser cannot render the image (e.g. unsupported codec).
  */
-export async function compressImage(file: File, quality = 0.82): Promise<CompressionResult | null> {
-  if (!COMPRESSIBLE_TYPES.includes(file.type)) return null;
+export async function compressImage(
+  file: File | Blob,
+  quality = 0.82,
+): Promise<CompressionResult | null> {
+  if (!isCompressibleType(file.type)) return null;
 
   const img = await loadImage(file);
   const canvas = document.createElement('canvas');
@@ -48,7 +55,7 @@ export async function compressImage(file: File, quality = 0.82): Promise<Compres
   });
 }
 
-function loadImage(file: File): Promise<HTMLImageElement> {
+function loadImage(file: File | Blob): Promise<HTMLImageElement> {
   return new Promise((resolve, reject) => {
     const url = URL.createObjectURL(file);
     const img = new Image();