WebM to MP4, in your browser
WebM is common online — it’s what many screen recorders and browser tools output — but it’s not universally accepted. Send a WebM to someone’s phone, drop it into a video editor, or share it in a messaging app and it often won’t play. Converting to MP4 (H.264) fixes that: MP4 is the format everything understands.
Mynify converts entirely in your browser, so your video is never uploaded to any server.
What to expect
MP4 conversion re-encodes the video to H.264 with AAC audio for maximum compatibility:
- The engine loads once (~30MB, cached afterwards).
- Longer videos take longer, since your device does the encoding — which is exactly why it stays private.
- The output plays on phones, computers, editors and TVs.
Tips
- Recorded a long screen capture? Trim it first to keep the conversion quick.
- Also handy: MKV to MP4 and MOV to MP4 for those formats.
Free, unlimited, no signup, no watermark — your video never leaves your device.