Convert MKV to MP4
Turn Matroska MKV recordings into MP4 for phones, TVs, editors and upload sites.
Files are processed on our server in Europe. Download links expire after 60 minutes; files are then deleted automatically.
Why use Video Compressor
Private and secure
Your video is sent over an encrypted connection to our server in Europe and stored under a random ID. It is never shared with third parties or used to train AI. Download links expire after 60 minutes; files are then deleted automatically, normally within 75 minutes. Read the privacy policy
Honest results
Choose quality and resolution. Progress comes from the encoder itself, and the result shows the exact size of your MP4 next to the original.
Free, no sign-up
Video Compressor is free with no account, no watermark and no ads. It works in any modern browser on phone or desktop.
In short
MKV to MP4 converts Matroska videos, such as OBS recordings, into MP4 with H.264 video and AAC audio. The first video and audio tracks are kept; subtitles and chapters are not carried over. Files up to 1 GB and 30 minutes are supported.
| Accepted formats | MP4, MOV, M4V, 3GP, WebM, MKV, AVI, WMV, FLV, MPEG, MTS/TS, OGV |
|---|---|
| Maximum file size | 1.00 GB |
| Output | MP4 (H.264 video, AAC audio), max 1080p, never upscaled |
| Video limits | Up to 30 minutes, up to 4K input |
| Target size | Not on converter pages; the video compressor sets target sizes |
| Units | 1 KB = 1,000 bytes; 1 MB = 1,000,000 bytes |
| Where files are processed | On our server in Europe; not sent to third parties |
| Retention | Download link expires after 60 minutes; files deleted automatically, normally within 75 minutes |
| Price | Free, no account, no watermark |
| Typical sources | OBS Studio and other screen recorders, HandBrake and MakeMKV output, downloaded videos |
| Codecs read | H.264, HEVC, VP9, AV1, MPEG-4 and MPEG-2 video; most audio codecs including Opus, Vorbis, AC-3 and FLAC |
How to use it
- Choose or drop your MKV file (up to 1 GB, 30 minutes), or import it from a link.
- Keep the High quality preset, or pick a lower resolution if you also want a smaller file.
- Select Convert to MP4 and keep the tab open while it uploads and converts.
- Preview the MP4 and download it.
Why convert MKV to MP4?
MKV is a flexible container that can hold many tracks, but iPhone, many smart TVs, video editors and social platforms don't accept it. OBS records to MKV by default because a crash can't corrupt it; converting afterwards gives you a file you can edit and share.
Tracks, subtitles and chapters
The MP4 contains the first video track and the first audio track. If your recording has several audio tracks (for example game audio and microphone on separate tracks), only the first one is kept. Subtitle tracks and chapters are not included.
Questions
Is MKV to MP4 conversion lossless?
No. The video is re-encoded to H.264, which is lossy, but converter pages start at the High quality preset, where the difference is hard to see at normal viewing size. The picture is never upscaled, and the shorter side is capped at 1080 pixels.
Can I keep my subtitles?
Not at the moment. Subtitle tracks are removed from the MP4. If you need them, extract them as a separate .srt file first.
What happens to my file after conversion?
It's stored under a random ID on our server in Europe. The download link expires after 60 minutes and the file is then deleted automatically, normally within 75 minutes. Canceling deletes it immediately.
Convert other formats to MP4
Related tools
- WebM to MP4Turn browser and screen recordings in WebM into MP4 that editors and phones accept.
- AVI to MP4Give old DivX and Xvid AVI videos a second life as MP4 that plays on phones and TVs.
- MOV to MP4Turn QuickTime MOV files from iPhone, Mac and cameras into MP4 that plays everywhere.
- Video compressorMake any video smaller, with a target size.
Last reviewed October 31, 2026.