Convert WEBM to MKV
Turn WEBM files into MKV in seconds — free.
- Works directly in your browser
- Keeps the original formatting and quality
- Download your file in seconds
- No signup, no watermark, no limits
- Supports batches of WEBM files up to 100 MB each
Upload your files
Drop WEBM files here
Files up to 100 MB · deleted automatically after 4 hours
How the conversion works
Three steps between your WEBM file and a finished MKV.
Add your WEBM file
Drag and drop it, or browse your device. Multiple files are fine.
Confirm MKV settings
Choose quality and naming, then start the conversion.
Download
Save the MKV file, or scan the QR code to grab it on your phone.
About converting WEBM to MKV
WEBM and MKV solve different problems, which is why this conversion is so common. Our converter reads the structure of your WEBM file and rebuilds it as a valid MKV file rather than simply renaming it, so the result opens cleanly in the apps you already use.
WEBM is an open video format designed for the web. MKV is a flexible open video container that can hold many audio and subtitle tracks.
The converter sits in our video converters toolkit alongside MP4, MOV, AVI, MKV, WEBM, FLV, WMV, MPEG and more. Nothing is installed, nothing is stored, and the output carries no watermark.