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WEBM to MKV Converter

Convert WEBM video to MKV locally in your browser with quality, resolution and frame-rate controls.

Drop WEBM videos hereUp to 10 files · 500 MB each · processed locally
No upload

AVAILABLE CONVERTERS

About WEBM and MKV

Learn about the source and output formats used in this WEBM to MKV conversion.

SOURCE FORMAT

WEBM

WebM is an open video format optimized for efficient playback on the web.

Open WEBM Converter
OUTPUT FORMAT

MKV

MKV is a flexible open container that can hold multiple video, audio and subtitle tracks.

Open MKV Converter
InputWEBM
OutputMKV
Best forvideo editing and publishing

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WebM ConverterMKV to WEBMWEBM to MP4WEBM to MOVWEBM to AVIWEBM to MPEGWEBM to M4VWEBM to GIF

About this tool

About WEBM to MKV

Use WEBM to MKV to change a WEBM video into MKV without installing desktop software. Add the source video above, adjust the available quality, resolution and frame-rate controls, then download the converted file.

Online webm to mkv conversion

The converter decodes the source and creates a new MKV file for compatible browsers and applications. Output size and processing time depend on duration, resolution, source codec and quality settings.

Local browser processing

Supported conversion runs on your device through the browser-based media engine. Keep the original video and check picture, sound and duration in the downloaded result before replacing an important source file.

Three simple steps

How it works

  1. 1
    Choose

    Add a supported file or paste your content.

  2. 2
    Process

    The tool works locally in your browser when supported.

  3. 3
    Download

    Save the result directly to your device.

Frequently asked questions

WEBM to MKV FAQ

How do I convert WEBM to MKV?

Choose a supported WEBM video, review the quality, resolution and frame-rate settings, start conversion and download the MKV result.

Are my files uploaded?

No. Supported video conversion runs locally in your browser, so the source file is not uploaded to zer.ai.

Will conversion change video quality?

Transcoding creates a new encoded file. Choose high quality when visual fidelity matters, or a smaller setting when output size is more important.