Free · WebM/MOV/MKV/AVI → MP4 · nothing uploads
Convert video to MP4
Screen recordings, downloads and camera files become a standard MP4 that plays on anything.
Why MP4/H.264 is still the answer
Newer codecs beat H.264 on pure compression, but compatibility is the feature that matters when you're sending a file to someone else's device. H.264-in-MP4 decodes in hardware on essentially everything made in the last decade: phones, TVs, browsers, editing apps, chat clients. When a video "doesn't work", converting to this combination is the fix nine times out of ten.
What happens to your file when you convert it
Every conversion here is a full re-encode. The video is decoded and compressed again as H.264 at a constant quality of CRF 21, in 8-bit 4:2:0 colour, and the audio becomes 128 kbps AAC. The MP4 is written with its index at the front, so it can start playing in a browser before the whole file has loaded. It downloads as your original file name with “-converted” added, and the original is never modified.
That makes it the right tool when the codec inside is the problem: a WebM screen recording, an MKV from a recorder, an old AVI, or an HEVC phone clip a PC will not open. If a MOV already holds H.264, a rewrap is faster and loses nothing, and the MOV to MP4 rewrap guide shows how to tell which case you have. 10-bit HDR phone footage comes out as 8-bit with its HDR colour tags kept but no tone mapping, so a player that ignores the tags can show it washed out; converting HEVC to H.264 covers that extra step.
The free version takes files up to 200 MB and adds a small corner mark to the export. Pro removes both.
Frequently asked questions
- Which formats can I convert?
- Anything your browser's FFmpeg build can decode: WebM, MOV, MKV, AVI, M4V and more. The output is always MP4 with H.264 video and AAC audio, the most compatible combination there is.
- Why won't my WebM screen recording play in some apps?
- WebM is a web format; plenty of native apps and older devices don't decode it. Converting to H.264 MP4 fixes playback almost everywhere, which is exactly what this tool is for.
- Does converting lose quality?
- Conversion re-encodes, so technically yes, but at CRF 21 the difference is rarely visible. The output is often smaller than the input as a bonus.
- Is my video uploaded anywhere?
- No. VidClip runs FFmpeg compiled to WebAssembly inside your browser. The file is read from your disk into the page's memory, processed there, and saved back to your disk. There is no upload, no server queue, and no copy of your footage anywhere but your machine.
- Is there a watermark?
- Free video exports carry a small semi-transparent VidClip mark in the corner. Audio-only output (MP3) has no watermark. Pro ($4/mo, billed $24 every 6 months · cancel anytime, or $79 lifetime, one payment) removes the watermark, lifts the 200 MB file cap, and adds instant lossless trim and mute.