🎬 Video Converter
MKV to MP4, MOV to MP4, anything to WebM or GIF — remuxed in seconds when the streams already fit the new container, re-encoded with a resolution and quality of your choice when they don't. Right in your browser.
About Video Converter
Drop in MP4, MKV, WebM, MOV, AVI, FLV, WMV, M4V, 3GP, MPG, TS, M2TS, OGV, VOB or GIF and pick an output: MP4, WebM, MKV, MOV, AVI, GIF, MPG, TS, WMV or OGV. Every file is identified by its actual contents, not its extension.
Remux first. When the video and audio inside your file are already legal in the target container — an H.264 MKV going to MP4, say — the streams are copied, not re-encoded: it takes seconds and loses nothing. Only when a stream genuinely has to change (WMV to MP4, anything to GIF, a lower resolution) does the tool re-encode, and it tells you roughly how long that will take before you start, so you can trade time for a smaller resolution or a faster preset.
The conversion runs on ffmpeg compiled to WebAssembly, entirely inside this tab: your files never leave your browser. The ~31 MB engine downloads once on first use and is cached afterwards. It runs on a single CPU thread, so re-encoding is slow compared with a desktop app — the estimate is there so you know what you are in for.
Up to 20 files · 1 GB per file · 2 GB per batch
🔒 Private — your files never leave this browser.
✂️ Trim (optional)
90 (seconds), 1:30 or 0:01:30.5. Leave a field empty to keep that end. The same trim applies to every file in the batch. A trim on a copied stream cuts at the nearest keyframe (up to a few seconds early); a re-encode cuts exactly.| Container | Re-encodes to | Copies without re-encoding |
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Input: MP4, M4V, MOV, 3GP, MKV, WebM, AVI, FLV, WMV/ASF, MPG/MPEG, VOB, TS/M2TS, OGV, GIF and most other containers ffmpeg reads, with H.264, H.265/HEVC, VP8, VP9, MPEG-1/2/4, Xvid/DivX, WMV, VC-1, Theora, ProRes, MJPEG, DV, FLV and more inside. AV1 can be copied into MP4/MKV/WebM but not decoded here, so it cannot be re-encoded or turned into a GIF. The first video and first audio track are kept; subtitles and extra tracks are dropped.
Limits: 20 files per batch, 1 GB per file, 2 GB per batch (the result has to fit in the tab's memory, which a 1 GB remux does). Files convert one at a time. A remux runs at hundreds of MB per second; a re-encode runs single-threaded — roughly 3–10× slower than real time at 1080p, which is what the estimate tells you before you start.
🔒 Everything runs locally in your browser with ffmpeg.wasm. No file, filename or metadata is uploaded to any server, and there is no analytics on this page.