Step 1: Attach your FLAC files using the button above or by bring and position.
Step 2: Click the 'Optimize' button to start the optimization.
Step 3: Collect your converted MKV files.
FLAC to MKV Optimization FAQ
Will the audio quality of my FLAC change in the MKV?
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The audio is re-encoded into the codec the MKV container expects (AAC for MP4/MOV, Vorbis/Opus for WebM, etc.), at a transparent bitrate by default. There is no second loss beyond that single transcode; the FLAC audio is not degraded by adding video.
Can I batch convert many FLAC files to MKV videos?
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Several files in one job need a paid plan. Free use is one file per conversion, one conversion an hour. On a paid plan you can add several files to one job, then download each result on its own or all of them in one ZIP.
How long does FLAC to MKV take?
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It depends on the size and length of the file. Small documents and images are usually ready quickly. Long videos take the longest, because most video conversions re-encode every frame.
Will the MKV video play on every device and platform?
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MP4 / H.264 plays essentially everywhere and is the safe default for uploads. MKV and WebM are better for some web players but less universal. Pick the MKV container your target platform documents as supported.
Is my FLAC file private during conversion?
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Yes. Uploaded FLAC files are processed on our own conversion servers, no person reviews them, and they are never shared. The upload and the converted MKV are both deleted automatically about 24 hours after the conversion, which leaves time to download the result. See /privacy/ for the full policy.
Can I loop or trim the FLAC before making the MKV?
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Trim the FLAC first with /audio-trim/, then convert the clip to MKV here. Looping is not built into the wrap step — prepare the exact audio you want, and the MKV matches its length precisely.
