Video Converter
Convert video between MP4, WebM, MKV, MOV, AVI, and more — or extract audio as MP3. Make clips play on any device, free and in your browser.
Popular conversions
All supported formats
The extension is the container, not the codec
A video file holds streams — usually one video, one audio, sometimes subtitles — each compressed with a codec. The extension tells you the container that holds them, not how they are compressed. An MP4 usually contains H.264 video and AAC audio, but it could contain H.265 or AV1 and still be an MP4.
This matters because it explains what a conversion costs. Every video conversion here is a full re-encode, not a container swap: the video is decoded back to pictures and compressed again with a fixed encoder profile for the target format. That takes real time and costs a generation of quality, and it is a deliberate trade — you get a predictable file that plays everywhere, rather than a fast copy carrying a codec the destination might not decode.
What each target is encoded with
| Target | Encoder settings |
|---|---|
| MP4 / M4V | H.264 at CRF 23, AAC 192 kbps, +faststart, yuv420p pixels |
| MKV | H.264 at CRF 23, AAC 192 kbps |
| MOV | H.264 at CRF 23, AAC 192 kbps, yuv420p |
| WebM | VP9 at CRF 32 constant-quality, Opus 128 kbps |
| AVI | MPEG-4 Part 2 at qscale 5, MP3 audio |
| 3GP | H.264 at CRF 28, AAC 96 kbps, yuv420p |
| MPEG / MPG | MPEG-2 at qscale 5, MP2 192 kbps |
| WMV | WMV2 at qscale 5, WMA v2 160 kbps |
| GIF | 12 fps, 480 px wide, 128-colour palette, Bayer dither |
Extracting audio and subtitles
A video does not only convert to other video. Choosing an audio target drops the video stream entirely and re-encodes only the audio — MP3, WAV, AAC, M4A, FLAC, OGG, or Opus — which is how you get a podcast episode or a soundtrack out of a recording.
Choosing a subtitle target is different again: no transcoding happens at all. The first subtitle stream inside the container is mapped out and rewritten as SRT or VTT. Both of these are checked before the job starts — we probe for an audio stream before an audio target and a subtitle stream before a subtitle target, so a silent recording or a video with burned-in subtitles fails fast with a clear message rather than handing you an empty file.
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Frequently asked questions
- Why does converting MP4 to MKV take so long?
- Because it is a full re-encode rather than a remux. In principle the streams could be copied into a new container in seconds, but every target here uses a fixed encoder profile so the output is predictable and plays everywhere. The cost is encoding time and one generation of quality.
- Do subtitle and audio tracks survive a video conversion?
- One video stream and one audio stream make it into the output. Additional audio tracks, embedded subtitle tracks, and chapter markers are not carried across. Extract subtitles separately as SRT or VTT if you need them.
- Why is my AVI bigger than the MP4 it came from?
- AVI is written with MPEG-4 Part 2 rather than H.264, because that is what legacy AVI players and editors actually decode. It is a weaker codec, so at comparable quality the file is usually larger. Convert to AVI when something specifically requires AVI, not for quality.
- Why is my GIF so large and banded?
- GIF stores every frame as a 256-colour palette image. We cap it at 12 fps and 480 px wide with a 128-colour palette to keep it manageable, but long clips still grow fast and gradients band visibly. GIF suits short clips of flat graphics and screen recordings, not footage.
- Is the Video Converter free?
- Yes, every conversion is completely free with no account and no watermark.
- Do I need to install anything?
- No. Use the tool from your browser; files are uploaded to our servers for processing.
- Are my files safe?
- Files are auto-deleted after 2 hours and are never shared.