Browser edition: files stay on your device. Up to 100 MB total and 10 minutes. First use downloads a 32 MB engine. Some formats depend on codec support. Public-link downloading is not ready on this free deployment.
Convert MKV to MP3
Convert MKV to MP3 online for free. Extract the audio track at the bitrate you choose.
How to convert MKV to MP3
- Add your fileDrop it on the page, choose it from your device, or paste it with Ctrl+V.
- ConvertAdjust settings if you like, then press the button. You'll see live progress.
- Browser processing uses original files on your device. Public-link downloading is unavailable.
What happens to your file
MKV files are common for archiving movies, OBS recordings, multi-language video, but not every app or device opens them. MP3 is ideal for music libraries, podcasts, car stereos, any device. Spool converts MKV to MP3 with FFmpeg — real decoding and encoding, not a renamed file extension.
Audio only. Spool drops the video stream and keeps the soundtrack. The audio is encoded to MP3 at the bitrate you choose (192 kbps by default). Tags such as title and artist are carried over when present.
Settings
- Audio bitrate — 320 kbps · best, 256 kbps, 192 kbps · standard, 128 kbps · small, 96 kbps, 64 kbps · voice
- Channels — Original, Mono
- Sample rate — Original, 48 kHz, 44.1 kHz, 22 kHz
MKV vs MP3
| MKV | MP3 | |
|---|---|---|
| Full name | Matroska Video | MPEG-1 Audio Layer III |
| Created by | Matroska.org (open standard), 2002 | Fraunhofer IIS / MPEG, 1993 |
| Type | Video container | Lossy audio |
| Typical contents | almost any video codec (H.264, HEVC, VP9, AV1) with any audio codec | MP3 (lossy) |
| Best for | archiving movies, OBS recordings, multi-language video | music libraries, podcasts, car stereos, any device |
| Strength | Holds multiple audio and subtitle tracks | Universal compatibility |
| Weakness | Not supported by iPhone, many smart TVs, Premiere and most social networks | Lossy: some detail is discarded |
About MKV
- Type
- Matroska Video
- Contains
- almost any video codec (H.264, HEVC, VP9, AV1) with any audio codec
- Use
- archiving movies, OBS recordings, multi-language video
About MP3
- Type
- MPEG-1 Audio Layer III
- Contains
- MP3 (lossy)
- Use
- music libraries, podcasts, car stereos, any device
FAQ
What bitrate should I choose for MP3?
192 kbps is a good default for music. Choose 320 kbps for the best quality, 128 kbps for podcasts and voice, 64 kbps for small voice notes.
Can I convert several MKV files at once?
Yes. Drop up to 10 files at a time — each one is converted in parallel and you can download them individually or all at once.
Is there a file size limit?
Convert and edit files on your device. The browser edition accepts up to 100 MB total, media up to 10 minutes and video up to 4K. Codec availability and device memory can limit individual jobs.
Is this MKV to MP3 converter free and safe?
Yes. There are no pop-ups, redirects or fake download buttons, and no software to install. Files are transferred over HTTPS, processed in isolated job folders and deleted automatically.