Does converting AVI to MKV lose quality?

No — if you use the remux method (copy codecs), quality is identical to the original. Quality loss only occurs if you choose to re-encode the video stream with a different codec.

Do I need to install anything?

Yes. FFmpeg is a free, open-source tool available for Windows, macOS, and Linux. Download it from ffmpeg.org and add it to your system PATH.

How long does conversion take?

A remux (stream copy) is nearly instant — often faster than real-time. Re-encoding with H.265 can take 1–5x the video duration depending on your CPU or GPU.

Will my subtitles be preserved?

Subtitles embedded in AVI (rare) are preserved during remux. External subtitle files (.srt, .ass) can be added to the MKV using the -i flag in FFmpeg.

What is the difference between AVI and MKV?

AVI is a 1992 Microsoft format limited to one audio/video stream and minimal metadata. MKV is a 2002 open standard supporting unlimited tracks, subtitles, chapters, attachments, and all modern codecs.

Can I batch convert multiple AVI files?

Yes. On Linux/macOS: for f in *.avi; do ffmpeg -i "$f" -c copy "${f%.avi}.mkv"; done. On Windows CMD: for %f in (*.avi) do ffmpeg -i "%f" -c copy "%~nf.mkv"

AVI to MKV Converter

Name: AVI to MKV Converter
Availability: InStock
Author: Nham Vu

Learn how to convert AVI video files to MKV format using FFmpeg commands, with a format comparison table and interactive command builder.

FFmpeg Command Builder

Fill in the fields and get a ready-to-run FFmpeg command.

Input filename

Output filename

Conversion mode

Audio handling

Generated Command

ffmpeg -i video.avi -c copy video.mkv

Remuxes the AVI container into MKV without re-encoding. All streams are copied as-is — lossless and very fast.

AVI vs MKV — Format Comparison

Feature	AVI	MKV
Released	1992 (Microsoft)	2002 (Open source)
Audio tracks	1 (limited)	Unlimited
Subtitle tracks	Very limited	Unlimited
Chapter support	No	Yes
Codec support	Limited (DivX, Xvid)	All codecs (H.264, H.265, AV1...)
File size overhead	Small	Negligible
Open standard	No (Microsoft)	Yes (Matroska)
HDR / metadata	No	Yes

Quick FFmpeg Reference

Remux (lossless, fastest)

ffmpeg -i input.avi -c copy output.mkv

Re-encode to H.264 + AAC

ffmpeg -i input.avi -c:v libx264 -crf 23 -c:a aac output.mkv

Re-encode to H.265 + AAC

ffmpeg -i input.avi -c:v libx265 -crf 28 -c:a aac output.mkv

Add external subtitle file

ffmpeg -i input.avi -i subs.srt -c copy -c:s srt output.mkv

Batch convert (Linux/macOS)

for f in *.avi; do ffmpeg -i "$f" -c copy "${f%.avi}.mkv"; done

Copied!

Summary

Learn how to convert AVI video files to MKV format using FFmpeg commands, with a format comparison table and interactive command builder.

How it works

AVI files store video and audio streams inside a Microsoft RIFF container with limited codec and metadata support.
MKV is a flexible container that wraps the same streams without altering the codec data — called a remux.
FFmpeg reads the AVI container, extracts the raw streams, and places them into an MKV wrapper with no quality loss.
Use the command builder below to generate an FFmpeg command tailored to your conversion goal.
Run the command in your terminal; conversion typically completes in seconds for a remux.

Use cases

Remux AVI files to MKV to add subtitle tracks or multiple audio streams.
Improve compatibility with modern media players that handle MKV better than AVI.
Preserve original video quality by avoiding re-encoding during container switch.
Add chapter markers or metadata not supported in the AVI format.
Reduce file size by re-encoding with H.265/HEVC inside an MKV container.
Archive video collections in a future-proof open-standard format.
Enable hardware-accelerated playback on devices that support MKV but not AVI.
Batch-convert an entire AVI library to MKV with a single FFmpeg command.

Frequently Asked Questions

Last updated: 2026-06-11 · Reviewed by Nham Vu