Convert MOV, AVI, MKV and WebM to MP4 (and back) right in your browser. Fast, quality-preserving, no upload and no signup.
Drop a video or click to browse
MOV, AVI, MKV, WebM → MP4 (and back) — fast, in your browser
100% in your browser — your video never leaves your device · up to 500 MB
Drop your video
Drag and drop a MOV, AVI, MKV, WebM or MP4 file. It is read locally and never uploaded.
Pick the output format
Choose MP4 (plays everywhere), WebM (smaller, for the web), MOV or MKV.
Convert and download
Conversion runs locally via WebCodecs. When only the container changes, it is near-instant. Then download your file.
MP4 with H.264 is the safest format for sharing — it plays on every phone, browser and app. Convert to it whenever you are unsure. Compress it too
When only the container changes (like MOV to MP4 with H.264), SammaPix remuxes the stream instead of re-encoding, so the conversion is near-instant with zero quality loss.
The conversion runs entirely on your device via WebCodecs. Your video is never sent to a server, so it stays private and there is no upload wait.
Convert between MP4, WebM, MOV and MKV. MP4 with H.264 plays on every device, so it is the safe default for sharing anywhere.
MOV is Apple's container, used by iPhones and QuickTime. It is excellent for editing but not always accepted by Windows apps, Android phones, or web uploads. MP4 is the universal container: it plays on essentially every device and platform made in the last fifteen years. Converting MOV to MP4 usually keeps the same H.264 video inside a different wrapper, which means SammaPix can simply rewrap the stream without re-encoding, finishing almost instantly with no quality loss.
If the source video codec already fits the target container (MOV H.264 to MP4, for example), SammaPix copies the stream directly, which is near-instant. When the codec is not compatible with the target, such as an old AVI with MPEG-4 or a WebM with VP9 going to MP4, it re-encodes to H.264 using your device's hardware via WebCodecs, which is still fast.
No. Unlike most online converters that send your file to a server, SammaPix does the whole job in your browser. Your video never leaves your device, which is faster and completely private.