Video

Convert WebM to MP4 Online — Free

WebM (VP8/VP9 video, Opus audio) is the modern web's open video format, but it doesn't play natively on iOS or in many editing tools. ReFile re-encodes WebM to standard H.264/AAC MP4 for universal compatibility.

No signup to try
Sandboxed processing
Files deleted in 24 h

What this does

Default: H.264 video + AAC audio (works everywhere)
Keep the original quality — 'high-quality MP4'
Strip the audio for a silent video — 'video only, no audio'

How it works

1
Upload your WEBM
Drop it above, or click to pick from your device. We validate the format immediately — no spinning on a file we can't process.
2
Run the conversion
The recipe runs in an isolated cloud sandbox — same as every other ReFile job. No AI guessing involved; it's a hand-written command that does one thing.
3
Download the MP4
Result lands in seconds. Files auto-delete from our servers after 24 hours; signed download URLs expire in the same window.

Frequently asked

Will I lose quality re-encoding?: WebM and MP4 use different video codecs, so a re-encode is required. ReFile uses a high-quality CRF (constant rate factor) by default — perceptually identical to the source for most content.
Why not just keep WebM?: If your target supports WebM, you should — it's smaller and modern. The MP4 conversion exists because most non-web players, especially on iOS, don't support WebM.

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How it works

Upload your WEBM

Drop it above, or click to pick from your device. We validate the format immediately — no spinning on a file we can't process.

Run the conversion

The recipe runs in an isolated cloud sandbox — same as every other ReFile job. No AI guessing involved; it's a hand-written command that does one thing.

Download the MP4

Result lands in seconds. Files auto-delete from our servers after 24 hours; signed download URLs expire in the same window.

Frequently asked

Will I lose quality re-encoding?

WebM and MP4 use different video codecs, so a re-encode is required. ReFile uses a high-quality CRF (constant rate factor) by default — perceptually identical to the source for most content.

Why not just keep WebM?

If your target supports WebM, you should — it's smaller and modern. The MP4 conversion exists because most non-web players, especially on iOS, don't support WebM.