Question 1

Why is trimming sometimes slightly off?

Accepted Answer

By default the clip is cut without re-encoding, which is very fast but can only start on a keyframe. Turn on "Frame-accurate" to re-encode the video for an exact cut, at the cost of speed.

Question 2

Is my video uploaded anywhere?

Accepted Answer

No. ffmpeg runs inside your browser, so the video never leaves your device. The ffmpeg engine itself (about 30 MB) is downloaded the first time you use a video tool.

Question 3

What file sizes work best?

Accepted Answer

Everything is held in your device's memory, so short clips and files under a few hundred MB work best. Very large files may fail on low-memory devices.

Video Trimmer

How to trim a video

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