Convert MP4 to MKV for Multi-Track Archival
Convert your MPEG-4 Part 14 files to Matroska Video online for free. MP4 can sometimes lack multi-track or subtitle support found in flexible containers like MKV — MKV solves that. No registration, no watermarks, instant download.
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Max 100 MB • Max 10 min duration • Max 1080p
How to Convert MP4 to MKV — 3 Steps
FFmpeg re-encodes your MP4 file to H.264, H.265, or VP9 MKV — multi-track archival.
Upload your MP4 file
Select your MP4 file from cameras. Files up to 100 MB and 10 minutes in duration are accepted.
Confirm and convert
Confirm you own the file and click Convert to MKV. Processing typically completes in under 60 seconds.
Download your MKV file
Download your MKV immediately — ready to store multiple audio tracks (e.g. different languages) in one file.
Why Convert MP4 to MKV?
MP4 (MPEG-4 Part 14) can sometimes lack multi-track or subtitle support found in flexible containers like MKV. Converting to MKV gives you multi-track and subtitles.
Frequently Asked Questions
Why convert MP4 to MKV?
MP4 (MPEG-4 Part 14) can sometimes lack multi-track or subtitle support found in flexible containers like MKV. Converting to MKV gives you store multiple audio tracks (e.g. different languages) in one file.
Will I lose video quality converting MP4 to MKV?
Our converter outputs H.264, H.265, or VP9 video at high-quality settings. When re-encoding is required, we use settings that minimise visible artefacts. The resulting MKV file will be visually very close to the original.
What MP4 files can I upload?
You can upload MP4 files from cameras, phones, screen recorders, and video editors. Files must be under 100 MB, under 10 minutes in duration, and not exceed 1080p resolution.
What is the maximum file size for MP4 to MKV conversion?
The maximum upload size is 100 MB and the maximum video duration is 10 minutes. Resolution is capped at 1920×1080 (1080p).
Is my MP4 file kept private?
Yes. Files are processed privately and automatically deleted within 60 minutes. We never store, sell, or analyse your content.
MP4 & MKV Format Guides
Understand the formats you're converting between — specs, pros, cons, and use cases.
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