Two modes, honestly explained
Instant copies the video stream without touching it: the cut lands on the nearest keyframe, which on phone recordings can sit a second or two before the point you picked. In exchange you get a cut that finishes in a blink on an hour-long file and loses exactly zero quality — the bytes are the original bytes.
Precise decodes and re-encodes the fragment: the cut lands exactly on your frame, at the cost of normal conversion speed and one re-encoding generation. Tools that promise instant and frame-accurate cuts without re-encoding are quietly doing one of these two things — physics offers no third option. Both modes run entirely in your browser.
Frequently asked questions
Why did my clip start slightly earlier than I asked?
You used Instant mode, which can only cut on keyframes — video is stored as rare full frames plus differences between them. Use Precise mode when the exact frame matters.
Which formats can I trim?
MP4, MOV, M4V, WebM and MKV. Instant mode keeps the original format; Precise mode outputs MP4, which plays everywhere.
Is there a length or size limit?
Only your device's memory. Instant mode handles hour-long recordings comfortably since it never decodes the video.