Convert MKV to WebM
Upload an MKV file and convert it to WebM. When the codecs already fit the target container, the conversion is lossless and near-instant; otherwise the video is re-encoded.
Upload an MKV file and convert it to WebM. When the codecs already fit the target container, the conversion is lossless and near-instant; otherwise the video is re-encoded.
WebM is technically a constrained Matroska, but it admits only VP8, VP9, and AV1 video with Opus or Vorbis audio. MKVs holding those codecs convert by lossless copy; the common H.264 variety is re-encoded to fit, at high quality.
When your MKV already contains WebM-legal codecs like VP9 and Opus, the streams are copied straight across.
Browsers play WebM natively in the video tag; MKV they do not. Same family, different table manners.
No, processing is local to your browser.