AVI to MKV Converter
AVI is a dated container with limited support for modern features like soft subtitles, chapter markers, and multiple audio tracks. Converting AVI to MKV upgrades your video files to a modern open-source container that handles all of these features while preserving your original video and audio quality intact.
Converting AVI to MKV is a remuxing operation that moves the existing video and audio streams into the Matroska container. No re-encoding happens, so your original quality is preserved bit-for-bit regardless of the codec used in the AVI source.
How to Convert AVI to MKV
- 1
Drop your AVI file into the upload area or browse to select it.
- 2
Choose MKV as the target output format.
- 3
Click Convert and download your modernized MKV file.
AVI vs MKV — Format Comparison
| Feature | AVI | MKV |
|---|---|---|
| Full Name | Audio Video Interleave | Matroska Video |
| Type | Video | Video |
| Codec | DivX / Xvid / H.264 / Uncompressed | H.264 / H.265 / VP9 / AV1 |
| Lossless | No | No |
| Extension | .avi | .mkv |
| Best For | Legacy video archives | High-quality video archival |
AVI Strengths
- Wide compatibility with legacy systems
- Simple file structure
- Can contain uncompressed video for editing
MKV Strengths
- Open standard with no licensing fees
- Supports unlimited tracks (audio, subtitles, video)
- Excellent for high-quality video with multiple languages
Frequently Asked Questions
When to Convert AVI to MKV
- Upgrading an older AVI video collection for a Plex or Kodi library
- Adding subtitle and audio track support to legacy AVI files
- Migrating AVI archives to a modern, open-source format
- Organizing multi-language content by leveraging MKV's multiple track support
Related Conversions
About Our AVI to MKV Converter
This converter uses FFmpeg compiled to WebAssembly (WASM) to transform your AVI files into MKV format entirely inside your web browser. When you select a file for conversion, the processing happens locally on your device. Your file is never uploaded to any server, never transmitted over the internet, and never stored anywhere outside your own computer. This privacy-first architecture makes our tool safe for confidential and sensitive content — including legal recordings, medical files, financial presentations, personal media, and any other material you would not want on a third-party server.
The conversion process works by decoding the AVI input using FFmpeg's highly optimized decoders, then encoding the output in MKV format with carefully tuned settings that balance quality and file size. When possible, the tool uses stream copy mode to remux (rewrap) compatible streams without re-encoding, which preserves the original quality with zero generational loss. When re-encoding is necessary due to codec differences between the two formats, the converter uses high-quality encoding settings to minimize any visible or audible quality reduction.
Supported input formats include MP4, MOV, AVI, MKV, and WebM for video, with automatic detection of the codecs and parameters inside your source file. The output is optimized for maximum compatibility with modern devices and platforms including Windows, macOS, Linux, iOS, Android, smart TVs, and all major web browsers.
Why browser-based conversion is safer: traditional online converters require you to upload your file to a remote server, where it is processed by third-party infrastructure and then made available for download. This workflow exposes your data to interception during upload, unauthorized access on the server, unclear data retention policies, and potential data breaches. Professionals in regulated industries such as healthcare (HIPAA), legal (attorney-client privilege), and finance (SOX, GDPR) often cannot use server-based converters without violating compliance requirements. Our WebAssembly-powered approach eliminates all of these risks by ensuring your data never leaves the browser sandbox on your own device.
The tool handles files up to 500 MB on desktop browsers and 200 MB on mobile devices. No account registration, no software installation, and no recurring subscription is required. Conversion typically completes in seconds for small files and a few minutes for larger ones, depending on your device's processing capabilities. Once the conversion is finished, you can download the result immediately and the source data is discarded from browser memory.