Keep only the part of a video you need: cut off a long start, an unwanted end, or take a clip from the middle. Enter where the clip starts and ends, and choose how it is cut.
Accurate or fast
Videos are compressed in groups of frames. Each group starts with a keyframe, a complete picture; the frames after it only store what changes. That is why there are two ways to cut:
- Accurate decodes the video and encodes the clip again, starting on exactly the frame you chose. The quality is kept high, and the sound is re-encoded too so it starts with the picture. It takes as long as encoding the clip.
- Fast copies the compressed video and sound without re-encoding: no quality loss, and done in seconds even for long videos. A clip can then only start at a keyframe, so it starts at the keyframe at or before your start time, often up to a few seconds early. The result tells you where it really starts.
Use Fast to shorten long recordings or when the exact start doesn't matter; use Accurate for a clip that must begin on a particular moment.
Entering the times
Write times in seconds (75 or 75.5), minutes and seconds (1:15.5) or hours, minutes and
seconds (1:02:03). Leave the end empty to keep everything up to the end, or give a length
instead under “More options”. An end past the end of the video is simply the end.
Formats
Fast keeps the original format: MP4, MOV, MKV, WebM, AVI, WMV, FLV, 3GP, MPEG, VOB, TS/MTS, OGV and DV clips stay in their format, with every sound track and, in MKV, MP4, MOV and WebM, the subtitles. MXF clips are copied into MKV. RealMedia and Y4M can only be cut accurately.
Accurate saves MP4, MOV, MKV and WebM videos in the same format and everything else as MP4 (H.264 and AAC). Upright phone videos stay upright either way.
Uploads can be up to 2 GB and 3 hours. An accurate clip can be up to about 25 minutes of 1080p video, and longer at lower resolutions.