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Video Converters

MKV to MP4

Play MKV downloads on iPhone, Apple TV, smart TVs and in PowerPoint by moving the streams into an MP4 container — usually without touching the video data.

Runs in your browser when it can; large or unusual files use our EU server and are deleted within 1 hour.

Drop MKV files here

or click to browse · paste from clipboard · up to 8000 MB each

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Why convert MKV to MP4

Most MKVs contain H.264 or HEVC video and AAC or AC-3 audio, all of which MP4 can hold. Remuxing copies those streams into an MP4 in a fraction of the play time, and the picture is bit-for-bit identical.

MP4 cannot carry everything MKV can: DTS and TrueHD audio are converted to AAC, and text subtitles are either converted to MP4-compatible tracks or dropped. VP9 or AV1 video in MKV is re-encoded to H.264 for maximum compatibility.

How it works

  1. Drop MKV file onto the box above, click it to browse, or paste from the clipboard.
  2. Adjust the options if you need to — the defaults suit most cases.
  3. Press Convert. Small files are handled on your device; larger ones are sent to our server with a progress bar.
  4. Download the MP4 — individually or all at once.

About the formats

MKV · Matroska video · .mkv

An open container that can hold any codec plus multiple audio tracks, subtitles and chapters; popular for rips and downloads, unsupported by iPhone and many TVs.

  • MKV to MP4 keeps the video quality when the codec is H.264 or HEVC — only the container changes.
  • MP4 cannot carry every MKV feature: soft subtitles and some audio codecs (e.g. DTS) must be converted or dropped.
  • Most desktop players (VLC, MPV) play MKV; Safari, iOS and PowerPoint do not.

MP4 · MPEG-4 Part 14 video · .mp4

The video format that works everywhere: phones, TVs, browsers, social networks. Normally H.264 video with AAC audio.

  • MP4 is a container; the codec inside (H.264, HEVC/H.265, AV1) decides what can play it.
  • H.264 MP4 is the safe choice for uploads and sharing; HEVC MP4 from newer iPhones needs extra codecs on Windows.
  • The “moov atom” placement decides whether a browser can start playing before the whole file downloads.

Related conversions

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Frequently asked questions