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How to convert WEBM to MKV?
You can convert WEBM to MKV with MConverter in three easy steps:
Choose WEBM files from your device
At the top of this page, drag and drop your WEBMs. You can also click to select WEBM files using your operating system's file picker. Another method is to press the keyboard shortcut Ctrl+V (⌘+V on Mac) to paste a WEBM file you have copied to clipboard. Converting a folder with WEBM files to MKV is also supported: simply paste or drag and drop it.
Click or tap on MKV from the list of target formats
Alternatively, you can use the search field to quickly find the format you need, whether it's MKV or something else.
Download your MKV files, after MConverter has finished processing them
There's an option to automatically download the converted MKV files, so you don't have to press the download icon for each MKV. You may see a share icon as well. Use it to directly share the MKVs with other apps.
About the formats
Video file formats
WebM is a relatively recent video file format for storing high-quality, highly compressed videos with very little quality loss. Because it is also royalty-free, it is frequently used on the web for HTML5 video playback. Its container is based on a Matroska (MKV) profile. It used the VP8 and VP9 technologies for video, and Vorbis and Opus for audio.
Video file formats
MKV files are MatrosKa Video files. Like the Russian Matryoshka doll, which contains multiple smaller dolls nested inside each other, the MKV format can contain multiple video, audio, and subtitle tracks inside a single file. This makes it convenient to have one video with a number of audio and subtitle tracks in different languages, all inside a single playable file.
Common questions about converting WEBM to MKV
Can I convert WEBM to MKV in bulk?
Yes, MConverter supports batch converting of multiple WEBMs to MKVs simultaneously. You can even drag and drop folders containing WEBMs to convert to MKV. Pasting WEBM files and folders copied in the clipboard also works: use Ctrl+V.
Can I convert a WEBM file to MKV, if its size is 1 GB?
Yes, with MConverter Premium you can convert big WEBMs, up to 1 gigabyte each. The free version lets you convert files up to 200 MB. If you need to convert WEBM files over 200 megabytes, try MConverter Premium.
Is converting WEBMs to MKV safe with MConverter?
Yes, we encrypt your connection using industry standards. Plus, your WEBM files are only accessible by you. 24 hours after the conversion completes, they are automatically deleted from MConverter’s servers. You can also delete your WEBMs and other converted files immediately after finishing the conversion by clicking the bin icon. Join others who have trusted us to convert over 2,821,161 files so far.
How long does it take to convert WEBM to MKV?
For most videos, the wait could be a few minutes or less. However, MConverter also supports converting larger videos, meaning that it could take a while (up to over an hour, for example).
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