Convert AVI to MKV
Free AVI to MKV converter that runs entirely in your browser. No uploads, no signup required.
Drop AVI files here
or browse your device. Free, no signup required, no watermarks.
Files are processed on your device, never uploaded
Media conversions run on a full FFmpeg engine compiled to WebAssembly. The engine (~31 MB) downloads once on your first conversion, then everything runs locally.
Three steps
How to convert AVI to MKV
Add your files
Drop AVI files into the box above, or click it to browse. Add several to batch convert.
Convert
MKV is already selected as the output. Hit Convert. Your browser does the work locally.
Download
Save each converted MKV file. Pro ZIPs whole batches in one click.
Audio Video Interleave
AVI
AVI is the classic Windows video container, still common for archived footage and older camcorders.
Matroska video
MKV
MKV is an open container that can hold any codec, multiple audio tracks, and subtitles in one file.
Why convert AVI to MKV?
AVI is the classic Windows video container, still common for archived footage and older camcorders. MKV is an open container that can hold any codec, multiple audio tracks, and subtitles in one file. Converting from AVI to MKV gets you the best of the target format wherever AVI falls short, whether that's compatibility, file size, or what your apps and devices can open. With FormatFusion the switch takes seconds and your files stay on your device the whole time.
Questions
AVI to MKV: common questions
Is this AVI to MKV converter free?
Yes. It is completely free with no watermarks and no account required, for files up to 1 GB each. Convert one file or a hundred.
Is it safe to convert AVI files here?
Safer than any upload-based converter. The conversion runs locally in your browser, so your AVI files are never sent over the internet and never touch a server.
Will I lose quality converting AVI to MKV?
No. This conversion preserves your content, and MKV output keeps everything the format supports.
Can I convert multiple AVI files at once?
Yes. Free converts up to three AVI files at a time. FormatFusion Pro batches without limits and downloads whole runs as a single ZIP.
Does it work on iPhone and Android?
Yes. FormatFusion runs in any modern mobile or desktop browser. No app install needed.