Fix 'File Not Supported' Error on WhatsApp Web
Many users encounter the frustrating "the file you tried adding is not supported" error when trying to upload or send MP4/MOV files via WhatsApp Web. This usually happens because the video uses incompatible codecs (like HEVC/H.265) or profiles that the browser cannot process for upload. The solution is to re-encode the video to the universally compatible H.264 Baseline + AAC profile.
🔒 100% Private — Processed Locally
Unlike other websites, this tool runs entirely in your browser using WebAssembly. Your private videos are never uploaded to a server for processing. This ensures your message media remains absolutely private.
Step-by-Step Guide
- Drag and drop the video that WhatsApp Web won't accept (showing "File not supported").
- Wait a few seconds while FFmpeg re-encodes the file locally in your browser.
- Download the fixed MP4.
- Attach the new file to your WhatsApp Web chat — it will now upload and send successfully!
Technical Details
The converter runs the following FFmpeg command client-side:
ffmpeg -i input.mp4 -c:v libx264 -profile:v baseline -level 3.0 \
-c:a aac -b:a 128k -movflags +faststart -pix_fmt yuv420p output.mp4