1. Upload your WEBM file
Start by dragging and dropping your WEBM file into the upload area, or click to browse your device and select your file in the list.
WEBM to MKV Converter Online
Convert your WEBM (.webm) file to MKV (.mkv) in seconds straight from your browser. No installs. No watermarks. 100 % free.
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Why choose HappyScribe?
47+ Formats
Convert from WEBM to MKV but also 47+ other formats.
100% Free
No signups, no fees, no hidden restrictions. Convert WEBM to MKV directly in your browser for free.
Secure
We take your security seriously. All file transfers use 256-bit SSL encryption.
Online
No installs needed; convert WEBM to MKV right from your browser, on any device, anytime.
How to convert WEBM to MKV?
2. Choose MKV format
Next, pick MKV as the format you’d like to convert your video into. Alternatively, we support +47 formats that you can choose from. When you’re ready, hit the Convert button.
3. Download your converted MKV
Once the conversion is complete, you’ll get a download link right away. Just click to save the file to your device. It’s fast, easy, and doesn’t require any software installation.
What is a WEBM file?
WebM is a royalty‑free container designed by Google for the open web. It packages the Matroska profile with VP8/VP9/AV1 video and Vorbis/Opus audio, optimised for low overhead and HTML5 streaming. Announced at Google I/O 2010, WebM combined Matroska’s flexibility with On2’s newly open‑sourced VP8 codec. YouTube began offering WebM downloads the same year. Support grew as browsers added VP9 hardware decoding and will expand again with AV1.
What is a MKV file?
Matroska Video (MKV) is a flexible open container that can accommodate virtually any codec, multiple subtitle tracks, and chapter points. It is built on EBML (Extensible Binary Meta Language), a binary cousin of XML, allowing unlimited, self‑describing elements. The project began in 2002 after developer Steve Lhomme forked the failed MCF container. With the explosion of H.264 ‘fansubs’, MKV became the default wrapper for anime communities, bundling soft‑subs and styled karaoke effects. In 2013 Matroska was standardised within the IETF as the basis for WebM, cementing its longevity.
Free Online WEBM to MKV Converter
Need to convert your audio file from WEBM to MKV? It’s simple. Just upload your file, choose the output format, and click ‘Convert’. That’s it — no downloads, no complicated software, and no hidden costs. Our tool is designed to be fast, secure, and completely free, so you can turn your files into the format you need in seconds.
Whether you’re converting audio for sharing, editing, or playback on different devices, our converter ensures high-quality output every time. After your conversion, you’ll also have the option to transcribe video to text, making it easy to turn your MKV files into accurate, editable text in just a few clicks.
Frequently Asked Questions
How to open a WEBM file?
Chrome, Firefox, Edge, and Android open WebM natively. Safari plays WebM starting macOS 14 with AV1 hardware decoders. Older editors may require transcoding to ProRes or H.264 MP4.
How to open a MKV file?
VLC, MPV, and Kodi handle MKV flawlessly on every OS. Editing suites such as DaVinci Resolve import common codecs like H.264 or ProRes within MKV, but for delivery you may still export MP4. MKVToolNix lets you split, merge, and tag tracks without re‑encoding.
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