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Free Video Converter — MP4, WebM, MOV, AVI, No Upload

Convert video between MP4, WebM, MOV, and AVI entirely in your browser. FFmpeg-powered, no upload, no watermark — your files never leave your device.

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Drop a file here or click to browseMP4, WebM, MOV, AVI, MKV in — MP4, WebM, MOV, AVI out🔒 Processed on your device — never uploaded

Never upscales — only shrinks a larger source.

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Convert video formats without trusting a stranger's server

A video converter is one of the most-searched utilities on the web, and almost every result works by uploading your file to a cloud server. That's a strange default for personal recordings, work footage, or anything private. This converter runs the full FFmpeg engine in your browser via WebAssembly: pick a file, pick a format, and the transcoding happens on your own CPU with nothing transmitted anywhere.

MP4, WebM, MOV, AVI — when each one makes sense

MP4 with H.264 video and AAC audio is the universal donor — the right answer for sharing, uploading, and playback on unknown devices. WebM uses open, royalty-free codecs and embeds cleanly in web pages. MOV is the QuickTime container Apple tools prefer, and AVI keeps two decades of legacy Windows software happy. The container matters less than the codec inside it — which is why this tool re-encodes properly instead of just renaming the extension.

Built on FFmpeg — the engine everything else uses

FFmpeg is the open-source project that quietly powers most video software, from editing suites to streaming platforms. Running it as WebAssembly means you get the industry-standard decoder support (MKV, 3GP, camera formats, odd phone containers) without installing anything — and without granting any website custody of your files.

Preview before you commit, resize or mute in the same pass

Dropping a file in shows a player immediately, so you can confirm it's the right clip before spending time converting it — and the result plays back the same way once it's ready. The Resolution menu caps the output at 1080p or 720p in the same conversion (it only ever shrinks a larger source), and "Remove audio" strips the track with -an for silent web embeds — no separate compression or editing step needed.

When converting is not what you need

Every conversion here is a re-encode, which costs a little quality and can make an already-small file bigger. If you only want to cut a section out, the trimmer's Fast mode copies the video untouched and finishes in seconds. If the goal is a smaller file, use the compressor, which is tuned for size. Convert when the problem really is the format — a site, device or editor that will not accept what you have.

Part of a full on-device video toolkit

Need just a section of the video? Send the result straight to the trimmer with one click. Want it smaller without changing format? The compressor is one click away too. Need only the audio track? Same — the buttons next to Download carry the converted file over automatically, no re-selecting it or uploading it twice. Every tool runs on the same in-browser engine, downloaded once per session.

Frequently asked questions

Can I see the video before I convert it?
Yes — as soon as you drop a file in, a player appears so you can confirm it's the right clip and check orientation before spending time on the conversion. The output plays back the same way once it's ready, so you can verify the result before downloading.
Which format should I convert to?
MP4 (H.264) unless you have a specific reason otherwise — it plays on effectively every device, browser, and app made in the last fifteen years. WebM suits web embedding with open codecs, MOV fits Apple-centric workflows, and AVI exists mainly for legacy Windows software.
Are my files uploaded anywhere?
No. Conversion runs on a WebAssembly build of FFmpeg inside your browser. The only download is the engine itself (once, ~31 MB); your video is demuxed, re-encoded, and remuxed entirely on your own device.
Can I resize or remove the audio while converting?
Yes. The Resolution menu caps the output at 1080p or 720p (it only ever shrinks — a smaller source is never upscaled), and "Remove audio" strips the audio track entirely with -an, useful for silent web embeds or background loops. Both apply in the same conversion pass, no separate step.
What input formats does it accept?
Practically anything FFmpeg can read, which is nearly everything: MP4, MOV, WebM, AVI, MKV, 3GP, MTS, and most phone and camera formats. If a file fails, it's usually an unusual codec inside the container — try the High quality setting, which re-encodes rather than copies.
Does converting reduce quality?
Converting between lossy formats always re-encodes, which costs a small, usually invisible amount at the Standard setting (CRF 26). Choose High (CRF 20) when the output needs to survive further editing or another round of compression later.
Why does WebM take longer than MP4?
The VP8 encoder used for WebM is simply slower than x264 in a single-threaded WebAssembly environment. For long videos where you just need broad compatibility, MP4 is both the faster and the more portable choice.
How do I convert a MOV or MKV file to MP4?
Drop the file in, leave the output format on MP4 (H.264), and press Convert. The video is re-encoded to H.264 with AAC audio, which is the combination the widest range of phones, TVs, editors and upload forms accept. The container name is the least of it — a site that rejects your file is almost always objecting to the codec inside, which is why this tool re-encodes instead of just renaming the extension.
Which setting gives the smallest file, and which the best quality?
Standard (CRF 26) with Max 720p gives the smallest MP4; High (CRF 20) with Keep original size gives the best. Both are re-encodes, so a converted file can end up larger than a source that was already heavily compressed — if size is the goal rather than the format, the compressor is the better tool. The result card shows the exact size next to the original.
Is it really free, with no watermark and no sign-up?
Yes. There is no account, no daily quota, no watermark and no file-size cap set by the site. Because the conversion runs on your own device, nothing costs us anything per file, so there is nothing to ration. The practical limit is your browser's memory, which matters mostly for very large files on phones.
What can I do with the converted file afterwards?
The buttons next to Download send it straight into the trimmer, the compressor, or the audio extractor — the converted file carries over automatically, so there's no re-selecting it or waiting through a second upload.

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