LosslessCut

Cuts and concatenates media by copying streams — instant, and no generation loss.

What it does

LosslessCut operates on stream copies rather than re-encodes. Marking in and out points and exporting takes seconds regardless of file length, and the output is bit-identical to the source within the kept range. It also merges files, extracts individual streams, fixes container issues and edits metadata.

This is the right tool for the first pass on long footage — cutting a two-hour recording down to the usable ten minutes before anything touches an editor.

The one real limitation

Cuts land on keyframes. Asking for a frame-exact cut between keyframes means either accepting the nearest keyframe or letting it re-encode that segment. For a rough cut that never matters; for a precise edit, do it in an NLE.

Notes

It is a GUI over ffmpeg, so anything it does is reproducible on the command line — it just spares you constructing the invocation.

Alternative to

Alternative	Type	Trade-off
`ffmpeg -c copy`	—	Exactly what LosslessCut runs, minus the timeline
Avidemux	Open source	Similar keyframe-based cutting, an older interface
QuickTime Player	Built in	⌘T trims without re-encoding, one clip at a time