How to Compare Two MKV Video Files

MKV is a container, not a guarantee

MKV (Matroska) can hold almost any video and audio codec combination, which is exactly why two MKV files with the same filename, similar size, and the same runtime can still be meaningfully different — a different source rip, a re-encode at a different CRF, a re-mux that dropped a track, or a “remastered” release that changed more than it should have. The container tells you nothing about what’s actually inside until you look at the frames.

Compare two MKV files in three steps

DiffALL decodes and analyzes the actual video content, not just the container metadata:

Upload both MKV files — the reference and the one you’re checking.
Get frame-by-frame analysis — SSIM and PSNR scores computed per frame, with a synchronized heatmap overlay showing exactly which pixels changed and when.
Read a similarity score — a single number for overall closeness, backed by a per-second timeline so you can find the worst moments fast.

What the results show you

Synchronized heatmap overlay — play both videos side by side with the differences highlighted live, so you don’t have to scrub for the moment something changed.
SSIM and PSNR per frame — the two standard objective video-quality metrics, computed automatically instead of eyeballed.
The exact second each difference appears — no manual scrubbing through a two-hour file hunting for the one changed shot.
A similarity percentage — a fast headline number before you dig into the frame-level detail.

Common use cases

Verifying a re-encode — confirm a re-compressed MKV still matches the source closely enough, and find exactly where quality dropped if it didn’t.
Comparing rips or releases — check whether two MKV releases of the same title are actually the same cut, or whether one has different edits, credits, or scenes.
Archival QA — confirm a re-muxed or re-packaged archive copy matches the original before you delete the source.
Catching unintended changes — verify that a batch re-encode job (codec change, resolution change) didn’t introduce artifacts or drop frames along the way.

Beyond MKV

The same engine handles MP4, AVI, MOV, WebM, and other common containers — so whether your files are MKV, MP4, or a mix of both, you get the same frame-by-frame heatmap and similarity score.

Try it now

Don’t judge two MKV files by their filename and size. Upload both and let DiffALL show you, frame by frame, exactly what’s different.