MKV to MP4
Converter
Convert Matroska (.mkv) videos to MP4 — the format that plays on phones, iOS Safari, video editors, and every social platform. Lossless container swap when possible; re-encoded only when needed.
Convert MKV to MP4 free →No account needed · Up to 25 MB free, 500 MB on Pro · Files permanently deleted after 1 hour
How it works
Common questions
Will the quality drop?
If your MKV already uses MP4-compatible codecs (H.264 or H.265 video + AAC audio), we copy the streams into an MP4 container — no re-encoding, no quality loss. If a codec needs converting (e.g. VP9 video), we re-encode at a high-quality setting; the difference is usually invisible.
Why does MKV not play on my phone?
iOS doesn't support the MKV container natively, and many Android players are unreliable with MKV. MP4 (with H.264 + AAC) is the format with the broadest device support, so converting solves the playback problem in one step.
How long does conversion take?
Container-only swaps (the fast path) finish in 5–15 seconds. Full re-encodes scale with video length — typically real-time or faster on our servers. A 10-minute 1080p video takes 1–3 minutes.
Are subtitles and multiple audio tracks preserved?
Audio tracks: yes, all of them. Subtitle tracks: only soft subtitles in compatible formats (SRT, TX3G) are kept in the MP4. PGS/VobSub subtitle streams have to be burned in or dropped — we currently drop them. If subtitle preservation is critical, mention it in your support email.