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AVI to MKV · Free

Convert AVI to MKV

Turn your AVI file into an MKV that plays where you need it, right in your browser.

  • Free to start
  • In your browser
  • Up to 500 MB
How it works

How to convert AVI to MKV

  1. Upload your AVI file

    Drag and drop an AVI file, or click to browse. Up to 500 MB, and nothing is installed.

  2. Confirm MKV as the output

    MKV is already selected, so there is nothing to configure. Switch to another format in the panel if AVI needs to go somewhere else.

  3. Convert and download

    We convert the AVI on our servers, usually in under a minute. Create a free account to download the MKV, or keep editing it in REQO.

Why convert AVI to MKV?

AVI is a Microsoft container from 1992. It still turns up in old archives, camcorder dumps and downloaded footage, but it predates modern compression and has no idea what a phone is.

The practical problem: Phones, browsers and social platforms do not play AVI at all. The legacy codecs inside waste enormous amounts of space compared with H.264. No support for modern features like proper streaming, chapters or clean seeking.

MKV solves that. Keeps multiple audio and subtitle tracks in one file.

Container

AVIAudio Video Interleave (Microsoft)
MKVMatroska

Typical codecs

AVIDivX, Xvid, MJPEG and other legacy codecs
MKVAlmost anything: H.264, HEVC, AV1, VP9

Best for

AVIOpening archive footage from the 2000s
MKVArchiving with multiple audio and subtitle tracks

Plays on

AVIDesktop players with the right codec pack
MKVVLC and desktop players; rarely anywhere else

File size

AVIVery large for the quality
MKVDepends entirely on the codec inside
FAQ

AVI to MKV questions

Is the AVI to MKV converter free?

Yes. Convert and preview the result for free, then create a free account to download it. There is no per-file charge and no watermark on the MKV itself beyond the free-plan badge.

Do I need to install any software?

No. The conversion runs on our servers and the whole flow happens in your browser, so it works the same on Windows, macOS, Linux, iPhone and Android. Nothing to install at either end. Where AVI plays: Desktop players with the right codec pack. Where the MKV you get back plays: VLC and desktop players; rarely anywhere else.

Does converting AVI to MKV reduce the quality?

Converting re-encodes the video, so it is not bit-for-bit identical. We encode at a high quality target, which keeps the result visually indistinguishable from the AVI on normal viewing. What changes is the container and the codec. MKV holds: Almost anything: H.264, HEVC, AV1, VP9. Converting the same file back and forth repeatedly will eventually show, so keep your original.

How large a file can I convert?

Up to 500 MB per file, which is more footage in some formats than others. AVI: Very large for the quality. MKV coming back: Depends entirely on the codec inside. For anything bigger, trim or compress it first, both are free tools here.

Is my file kept private?

Your upload is processed and then held only as long as your project needs it. Nothing is published, indexed or shared unless you create a share link yourself.

Convert AVI to MKV now

Free, in your browser, and the file stays open in a full video editor afterwards.