How to trim a video
- Choose the video above. The preview loads with the file's length, picture size and codecs.
- Play or scrub to the first moment you want to keep, pause, and press "Start at playhead". Or type the time into Start.
- Move to the last moment you want and press "End at playhead", or type the End time.
- Leave "Exact cut" unticked for a fast, lossless copy, or tick it if the clip must begin on an exact frame.
- Press "Trim video" and download the result when it appears. Its name ends in "-trimmed".
Times can be typed as plain seconds (95.5), minutes and seconds (1:35.5) or hours, minutes and seconds (1:02:10). If the end is not after the start, the tool asks you to fix it before running.
Fast mode and Exact cut: keyframes in plain words
Compressed video doesn't store every frame as a full picture. Every so often there is a keyframe, a complete image; the frames in between store only what changed since the frames before them. A keyframe plus the frames that depend on it is called a group of pictures (GOP). How far apart keyframes sit depends on the camera or app that made the file: often a second or two, sometimes much longer in screen recordings and live-stream captures.
That matters for cutting. A clip can only start cleanly on a keyframe, because the frames after it need that full picture to make sense. The two modes deal with this differently:
- Fast mode (default)
- copies the compressed frames as they are. The start moves back to the nearest keyframe before the time you set, so the clip may begin slightly earlier. No quality loss, done in seconds, works without video encoding support.
- Exact cut
- decodes the frames and re-encodes them, so the clip begins on the exact frame you chose. Slower, depends on your device, and the picture goes through one more round of compression.
- Output format, fast mode
- same family as the input: MP4, MOV and M4V give MP4, WebM gives WebM, MKV gives MKV
- Output format, Exact cut
- MP4 (H.264 where the browser can encode it)
The keyframes and GOP structure article goes deeper if you want the full picture.
Which mode to pick
You want minutes 12 to 31 of a two-hour call to share with a colleague. A second of extra lead-in doesn't matter, so fast mode gives you the clip almost immediately with no loss.
The clip must open on the exact frame of a face or a punchline. Tick Exact cut; the wait is worth it for a short clip.
Several cuts from the same long file. Fast mode keeps each pass short; if one cut lands awkwardly, redo only that one with Exact cut.
The clip should open just as the cursor clicks a button, but fast mode started on an earlier keyframe and shows the end of the previous step. Run the same times again with Exact cut.
As a rule of thumb, use fast mode for anything long or for clips where a fraction of a second doesn't matter, and Exact cut for short, timed pieces. Re-encoding a long clip in a browser tab can take a while, so keep the tab open until the download appears.
Keeping subtitles in sync after a trim
If the video has an SRT or VTT file, trimming the start changes where every subtitle should appear. A line that showed at 12:40.0 in the original now belongs at 0:40.0 in a clip that starts at 12:00.0. Everything has to move back by the length you cut off.
- Note the real start of the trimmed clip. With Exact cut that is the time you typed. With fast mode it may be slightly earlier, so check the first frame of the result against the original before shifting subtitles.
- Open the subtitle timing shifter and move every line back by that amount, for example by minus 12 minutes.
- Lines that now have negative times belonged to the part you cut off; delete them, then check the result in the subtitle editor against the trimmed video.
For a short clip it can be simpler to make fresh subtitles from the clip itself with the subtitle generator. That costs 1 credit per minute with a minimum of 5 credits per file, so a 3-minute clip costs 5 credits (0.5¢), and new accounts start with 100 free credits.
Finding the part worth keeping
In a long recording, scrubbing to find the right moment is the slow bit. A transcript makes it faster: search the text for the topic, read off the timestamp, then type that time into Start. The guide to finding clips in long videos with transcripts shows the whole workflow.
More free tools
- Crop Video Online
- Convert Horizontal Video to Vertical (16:9 to 9:16)
- Resize Video to a New Size or Shape
- Resize Video for Instagram Reels, Stories and Feed
- Change Video Resolution: 4K to 1080p, 1080p to 720p
- Rotate Video 90° or 180°, or Flip It
- Mute a Video: Remove the Sound Track
- Change Video Frame Rate (60fps to 30fps and More)
- Speed Up or Slow Down a Video
- Blur Part of a Video
- Add Audio to Video: Replace the Soundtrack
Turn the file into text
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Frequently asked questions
Why does my trimmed clip start a little before the time I set?
In fast mode the cut has to begin on a keyframe, and the tool uses the nearest one before your start time. Tick Exact cut to start on the precise frame.
Does trimming a video lose quality?
Fast mode doesn't: the picture is copied as it is. Exact cut re-encodes the clip, which adds one more round of compression.
Can I cut a section out of the middle of a video?
Not in one step. Trim the part before and the part after as two clips, then join them in a video editor.
What time format do the Start and End fields accept?
Plain seconds such as 95.5, minutes and seconds such as 1:35.5, or hours, minutes and seconds such as 1:02:10.
How do I fix my SRT after trimming the video?
Shift every line back by the amount you cut from the start, then delete any lines that end up before zero. The subtitle timing shifter does the shift in one go.
Will a trimmed MKV stay an MKV?
In fast mode, yes: MKV stays MKV and WebM stays WebM. Exact cut always produces an MP4.