Convertr

Convert MKV to MP4 Online Free

Make an MP4 from a Matroska video. Each valid MKV starts its own upload and conversion job as soon as you choose it.

This page is shown in English because its translation has not been reviewed.

Convert a Matroska MKV video to MP4

Use this MKV to MP4 converter when a Matroska video will not play, upload, or import in the app or device you need. MP4 is a more widely supported container, but the codecs and streams inside a video still affect compatibility.

Choose one or more genuine .mkv files up to 1 GiB each. Each valid file starts an independent conversion job with its own upload progress, processing status, result, error, retry, and delete actions.

How MKV video is converted to MP4

MKV is the Matroska container and can hold different video and audio codecs, as well as subtitles and other tracks. When the source video and audio streams are compatible with MP4 and pass output checks, the worker remuxes them into an MP4 container without re-encoding.

If a compatible remux is not possible, supported video is encoded as H.264 at the source resolution and source audio is encoded as AAC when present. The worker verifies that required source streams remain in the output; if it cannot preserve them, the job fails visibly instead of silently claiming a complete conversion.

Source resolution and duration are kept

The fallback encode uses the source video resolution and duration. This page does not trim, resize, or change the source duration, and it does not offer codec, quality, bitrate, or audio settings.

A remux keeps compatible encoded streams unchanged. A fallback H.264/AAC encode does re-encode the media, so its visual or audio quality may differ from the original even though the source resolution and duration are retained.

Separate jobs and the 1 GiB file limit

Each selected MKV gets its own worker selection, upload, progress updates, and output. A problem with one file does not change another file's job. The upload limit is 1 GiB per file; larger files must be reduced outside this converter before upload.

When a conversion is complete, download the signed MP4 link. The worker removes the uploaded MKV after success; use the delete action to remove the converted MP4 before job expiry.

How to convert MKV to MP4 online

  1. Choose one or more MKV (.mkv) video files up to 1 GiB each.
  2. Each valid file starts its own MKV to MP4 job after a compatible worker is selected; no output settings are required.
  3. Follow each file's upload and conversion progress. If a file cannot be converted while preserving required streams, its job shows an error.
  4. Download the signed MP4 when it is ready, or use the delete action to remove the remaining converted output from the worker.

MKV to MP4 FAQ

Is this an MKV to MP4 converter?

Yes. Choose a Matroska video with an .mkv filename and the page starts one MP4 conversion job for each valid file. A filename extension alone does not guarantee that the contents are valid or convertible.

Can MKV be remuxed to MP4 without losing quality?

If the source video and audio streams are compatible with MP4 and the output checks pass, the worker can remux them without re-encoding. Otherwise, supported video is encoded as H.264 and source audio as AAC when present, which re-encodes the media and can change its quality.

Will the MP4 keep the MKV's resolution and duration?

The conversion keeps the source resolution and duration and does not trim or resize the video. A fallback encode uses H.264 at the source resolution; a compatible remux keeps the encoded streams unchanged.

Can I change bitrate, codec, quality, resolution, or trim the video?

No. This page runs a fixed MKV to MP4 workflow and does not expose bitrate, codec, quality, resize, trim, or audio settings.

What happens if the video's streams are not supported?

The worker tries a compatible remux or supported H.264/AAC fallback. If it cannot preserve the required source streams in the MP4, the conversion reports an error rather than silently dropping them.

How large can an MKV file be?

Each MKV upload can be up to 1 GiB. Reduce a larger video outside this converter before uploading it.

Can I convert multiple MKV files?

Yes. Select multiple files and each valid MKV starts an independent job with separate progress and a separate result. The 1 GiB limit applies to each file.

Can I delete the MKV upload after conversion?

The worker removes the uploaded MKV after a successful conversion. Use the delete action to remove the converted MP4 before the job expires; a failed job can use the same control to clear retained files.