Video Trimmer

Most of the time, trimming a video means keeping thirty seconds out of three minutes — the clip that matters, without the fumbling at the start and the walk back to the camera at the end.

By default this copies the frames rather than re-encoding them. That makes it almost instant even on a long video, and completely lossless: the frames written out are bit-for-bit the ones that were in the original. It is also why it is so much faster than compressing.

The catch is where it can cut. Copying can only start at a keyframe, and keyframes are typically a second or two apart, so the clip may begin slightly before the time you asked for. For most purposes that is fine and the speed is worth it. When it is not — when the cut has to be on a specific word or frame — there is an option to re-encode, which cuts exactly at the cost of real processing time.

Scrub the player to find your moment and read the time off it. Times can be written as seconds, or as minutes and seconds, or with hours if the video is long.

The whole thing runs in your browser using a WebAssembly build of ffmpeg served from this site. Nothing is uploaded, so the video never goes anywhere near a stranger's server.