Guides / How to merge (concatenate) videos on Mac without re-encoding

How to merge (concatenate) videos on Mac without re-encoding

Updated 2026-06-17 · Runs locally — nothing uploaded

Quick answer

Join multiple clips into one video on your Mac — instant and lossless when they match, no command line, nothing uploaded. One step with FFmix.

Output: Join videos
Processing: On your Mac
Setup: About 2 minutes to set up
Access: Free local task

Got a handful of clips that should be one video — screen-recording parts, camera takes, exported segments? You don’t need a full editor just to stick them end to end.

FFmix joins them in order with ffmpeg’s concat demuxer — instant and lossless when the clips match, re-encoded automatically when they don’t. It writes the file list for you, runs on your Mac, and uploads nothing.

Steps

1 Drag the clips into FFmix in the order you want them.
2 Pick the Join videos task — FFmix writes the concat list for you.
3 Confirm and click Start — the joined video saves next to the first clip.

Advanced: canonical ffmpeg recipe

This is the canonical recipe. FFmix adapts encoder flags to the engine on your Mac, then shows the final command; the command shown is the command run.

ffmpeg -f concat -safe 0 -i list.txt -c copy joined.mp4

FFmix has a one-click "Join videos" preset

Drop a file and go — all local, nothing uploaded.

Download FFmix free

FAQ

Can I merge videos without re-encoding?

Yes. When the clips share the same codec, resolution, and frame rate, FFmix joins them with `-c copy` — instant and bit-for-bit lossless. If they differ, it re-encodes so the result plays as one seamless file.

Do the clips need to be the same format?

For the instant lossless path, yes — same codec, resolution, and fps. FFmix detects a mismatch and re-encodes automatically, so mixed clips still merge cleanly.

Is anything uploaded?

No. Merging runs locally through the bundled ffmpeg engine; your clips never leave your Mac.

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