Convert Video Format
Convert videos between popular formats including MP4, WebM, MKV, AVI, MOV, and even animated GIF. Perfect for compatibility and sharing.
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Containers, codecs, and what conversion means
Two separate things are usually meant by "video format". The container — MP4, MOV, MKV, WebM, AVI — is the wrapper that holds the streams and their timing. The codec — H.264, H.265, VP9, AV1 — is how the picture itself is compressed. An MP4 file might contain H.264 or H.265 video, and that difference decides whether a given device can play it.
This matters because some conversions are nearly free and others are not. Repackaging the same streams into a different container — MKV to MP4, for instance — is a remux: no re-encoding, no quality loss, and it takes seconds. Changing the codec means decoding every frame and encoding it again, which is slow and always loses a little quality. If your problem is a container a player will not open, remuxing usually solves it without touching the picture at all.
Why we built this tool
Conversion is forced by compatibility: an editor that will not import a codec, a TV that only plays MP4, a website that rejects MOV, or a phone recording nothing on your desktop can open.
The files are personal footage and are frequently gigabytes in size, which is where free converters impose their limits and their watermarks. Ours uses WebAssembly FFmpeg in your browser, so the whole conversion runs locally: no upload, no cap on file size or duration, no account, and no branding on the output. On a long file that also means no waiting for an upload before the work even starts.
Tips and common mistakes
- Try a container change first; if the codec is already compatible, it is instant and lossless.
- H.264 in MP4 remains the most universally playable combination.
- Re-encoding always costs quality, so convert from the original rather than a converted copy.
- Check that audio and subtitle tracks survived the conversion.
Quick start: using Convert Video Format
- Load the video you want to convert.
- Choose the target container and, if needed, the codec.
- Prefer a straight container change when the codec is already compatible — it is far faster and lossless.
- Start the conversion and expect a full re-encode to take a while.
- Play the result on the device it was intended for.
Reduce the size afterwards with Compress Video, or pull out just the sound using Extract Audio from Video.