My video won't play (MOV, AVI, MKV)
iPhone MOV that won't open on Windows? An AVI your editor rejects? Convert it to MP4, the universal format.
When a video won't play or upload, it's usually the format. Converting MOV (iPhone), AVI, MKV or WebM to MP4 fixes it, because MP4 plays on virtually every device, editor and platform. Our converter runs in your browser, so the file is never uploaded. Convert once and it'll open where the original wouldn't.
4 tools for this
Each one is free, private and runs in your browser. No sign-up, no watermark.
MOV to MP4
Convert MOV (QuickTime) to MP4 in your browser, a universally compatible H.264/AAC file that plays and uploads everywhere. Real FFmpeg transcoding, in-page preview, one-click download. Nothing is uploaded.
Video Converter
Convert video between MP4, WebM, MOV, AVI, MKV and GIF in your browser with FFmpeg. Pick a target format, tune MP4 quality, preview the result and download. Nothing is uploaded.
Video Compressor
Compress video in your browser with FFmpeg, shrink MP4, MOV, WebM and MKV files with a simple quality slider, see the exact bytes and percentage saved next to a live preview, then download. Nothing is uploaded.
AVI to MP4
Convert AVI to MP4 (H.264/AAC) in your browser: the universal format that plays on phones, browsers, social and editors. Real transcoding with web-ready faststart, preview and download. Nothing is uploaded.
How to fix it
Follow these steps and you'll have it sorted in a couple of minutes.
- 1
Open the converter
Use MOV to MP4, or the general Video Converter for AVI, MKV, WebM and more. Drop your file in.
- 2
Convert to MP4
The tool re-encodes the video to MP4 (H.264), the most widely supported format.
- 3
Check it plays
Open the result to confirm it now works in your player, editor or upload form.
- 4
Compress if needed
If the MP4 is large for emailing or uploading, run it through the Video Compressor.
- Just renaming a.mov to.mp4. That doesn't re-encode it and it still won't play. Convert it properly.
- Processing a very large clip on a low-memory device. Browser conversion has limits, so trim first if it stalls.
- Converting to an obscure format when MP4 is the safest choice for compatibility everywhere.
Frequently asked questions
More problems we solve
Ran into one of these too? Here's the fix.
- My video is too large to send or uploadPhone videos get huge fast. Compress, resize or trim to fit an email or upload limit without a cloud service.
- I want to turn a video clip into a GIFGrab a few seconds of a video as a looping GIF for a chat, a doc or a reaction. No upload needed.
- I want to get the audio (MP3) out of a videoKeep only the sound (a lecture, a song, a podcast segment) as a clean MP3 you can play anywhere.
Keep exploring
Problems we solve
Definitions
From the blog
Compare formats
Common tasks
Ready? Start with MOV to MP4
Free, private and instant: everything runs in your browser.