FLV to MKV Converter

Convert FLV to MKV online. FLV and MKV are containers, while the video and audio codecs live inside them. Free batch processing with no signup or watermark.

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What changes when you convert FLV to MKV?

FLV and MKV are containers, while the video and audio codecs live inside them. Compatible streams may be copied; otherwise they are re-encoded for the selected MKV settings.

For the widest playback support, check that the selected video and audio codecs are accepted by the device or service that will receive the MKV file.

Add multiple videos and adjust the available video and audio codec settings before processing.

Open the finished MKV file and check fine details, layout and compatibility in the app where you plan to use it.

What is a FLV file?

FLV (Flash Video) was the format of web video during the Adobe Flash era. Flash is now discontinued and modern browsers no longer play FLV, so old FLV clips usually need converting to MP4 to be watchable today.

How to open a FLV file

FLV no longer plays in browsers; use VLC to view it, or convert it to MP4 for phones, editors and everywhere else.

What is a MKV file?

MKV (Matroska) is a flexible open container that holds high-definition video, multiple audio tracks and subtitles in one file. It is popular for movies and archiving, but is not natively supported by every device or browser.

How to open a MKV file

MKV plays in VLC and most modern media players; some phones, browsers and TVs need it converted to MP4 first.

Frequently asked questions

Is it free to convert FLV to MKV?

Yes. There is no sign-up, subscription or watermark on the converted file.

What happens to quality when FLV becomes MKV?

FLV and MKV are containers, while the video and audio codecs live inside them. Compatible streams may be copied; otherwise they are re-encoded for the selected MKV settings.

Which conversion options are available on this page?