Is Convert to MP4 free? Is there a watermark?

Yes — Convert to MP4 is free to use with no sign-up or watermark. Very large files can still be limited by your browser's available memory and processing resources.

Do my files get uploaded to a server?

No. Convert to MP4 runs entirely in your browser with WebAssembly, so your MOV, WebM, MKV, AVI, and more file never leaves your device and nothing is stored or seen by us.

What can I put in, and what do I get out?

Convert to MP4 accepts MOV, WebM, MKV, AVI, and more and gives you back a MP4 file. Actual codec support depends on what the bundled engine or browser decoder can read.

Will I lose quality converting to MP4?

The H.264 conversion is lossy rather than a reversible container change. Keep the source and compare motion, fine text, colour, and audio sync in the result.

Free tools · Convert

Convert to MP4

Convert common MOV, WebM, MKV, and AVI sources into H.264/yuv420p MP4 with AAC audio. Actual codec support varies. No upload or watermark.

Runs entirely in your browser. Your file is never uploaded — no watermark, no account.

Drop a file or click to chooseMOV, WebM, MKV, AVI, and more

Get a better result

Best for: Making a MOV, WebM, MKV, AVI, or other browser-selected video usable in an editor or platform that expects a conventional MP4 file.
Input → output: The primary source video and audio become H.264/yuv420p video with 128 kbps AAC audio in an MP4 container. The tool performs a full transcode rather than changing only the filename.
Quality tip: Try a short representative file first when the codec is unusual, then inspect fast motion, fine type, colour, and audio sync.
Know before running: Unsupported codecs can fail, and secondary audio tracks, subtitles, chapters, or attachments are not explicitly selected for preservation. Re-encoding introduces generation loss and cannot restore missing source detail.
Next step: Trim video to keep only the useful section after compatibility conversion.

How to use Convert to MP4

1
Choose your file. Drop a supported MOV, WebM, MKV, AVI, and more file into the tool, or click to select one. It stays on your device — nothing is uploaded.
2
Run locally. Press Run to begin. The first processing run loads the browser engine before local processing begins.
3
Download. Review the result, then download the finished file from your browser with no watermark.

Frequently asked questions

Is Convert to MP4 free? Is there a watermark?: Yes — Convert to MP4 is free to use with no sign-up or watermark. Very large files can still be limited by your browser's available memory and processing resources.
Do my files get uploaded to a server?: No. Convert to MP4 runs entirely in your browser with WebAssembly, so your MOV, WebM, MKV, AVI, and more file never leaves your device and nothing is stored or seen by us.
What can I put in, and what do I get out?: Convert to MP4 accepts MOV, WebM, MKV, AVI, and more and gives you back a MP4 file. Actual codec support depends on what the bundled engine or browser decoder can read.
Will I lose quality converting to MP4?: The H.264 conversion is lossy rather than a reversible container change. Keep the source and compare motion, fine text, colour, and audio sync in the result.