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Free Online M4V to MKV Converter

Convert M4V video to MKV online for free.

Drop M4V files here
or click anywhere in this box to choose files

Max file size 50MB. Sign up for more.

When MKV is the right output

MKV is an open container that holds essentially any codec — popular with archive-quality releases, multi-language / multi-subtitle content, and the ripping community. Convert to MKV when preserving multiple audio tracks or subtitle streams matters. Playback support is universal on desktop, variable on mobile / TV apps.

M4V vs MKV: Side-by-side

Technical comparison of the two formats — useful for deciding which to use, or for confirming what changes during conversion.

Property M4V MKV
Full name iTunes Video (MPEG-4) Matroska Video
Year introduced 2003 2002
Developer / standard body Apple Matroska Foundation
MIME type video/x-m4v video/x-matroska
File extension .m4v .mkv
Compression H.264 Codec-flexible (H.264, H.265, AV1, VP9)
Color / data depth 8-bit Up to 12-bit
Max dimensions / size Codec-dependent Codec-dependent
Transparency No No
Animation No No
Standard / specification Apple (MPEG-4 variant) Matroska
Best for Apple TV, iTunes movie purchases, iOS video High-quality video with multiple audio/subtitle tracks

M4V to MKV FAQ

Quick answers about compatibility, quality, metadata handling, and the most common reasons to convert M4V files to MKV.

How do I convert M4V to MKV?
Upload your M4V video to iFormat and click Convert. It's re-packaged into the MKV container with the optimal codec while resolution and frame rate are preserved. It's free and needs no account.

How do I open M4V files?
On Windows: Media Player or VLC. On a Mac: QuickTime and TV, natively. Apple's MP4 variant. Plays widely unless it carries FairPlay DRM from an iTunes Store purchase, which nothing outside Apple's apps will open.

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Video Conversion Guides for M4V to MKV Converter

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MKV vs MP4: Which Video Format Should You Use?

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MOV vs MP4: Which Video Format Is Better?

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