Does trimming reduce the quality?

Not if the cut starts at the beginning, because the frames are copied rather than encoded again. Starting partway in requires a re-encode, and the quality setting then decides how close to the original it stays.

Why did my clip start slightly before the handle?

A copied cut has to begin on a key frame, and those are a second or two apart. Choosing a quality instead of matching the original makes the cut frame accurate, at the cost of re-encoding.

Can I cut a piece out of the middle?

Not in one go. Trim the part before it and the part after it, then join them in an editor. This tool keeps one continuous section.

Is the sound trimmed too?

Yes, to the same range, and it stays in step with the picture. You can also remove it entirely, which is worth doing when the clip is going somewhere that plays muted anyway.

Trim Video

Drag the two handles to the part you want and save it. A cut that starts at the beginning copies the pictures across untouched, so it finishes almost at once and the quality is exactly the original's.

Choose a video or drop it hereMP4, MOV, WebM or MKV, up to 500 MB.

Runs entirely in your browser. Your files are never uploaded.

How to use Trim Video

1Choose a video, or drag it onto the box.
2Move the start and end handles. The preview follows whichever one you touched.
3Leave the quality on matching the original unless you want a smaller file.
4Trim, then download.

Why the start matters

A video is not a list of independent pictures. Most frames describe only what changed since an earlier one, and those chains begin at key frames, a second or two apart. Cutting between key frames means the frames after the cut have nothing to refer back to.

Which gives two ways to trim. Keeping the beginning means the chains are intact and the compressed frames can be copied straight into a new file, so the result is identical to the original and arrives immediately. Starting partway in means the pictures have to be decoded and encoded again, which takes real time and costs a little quality.

Both are offered here, and the page says which one your settings produce before you press anything. Taking the first five seconds out of a 20 second 720p file took 92 milliseconds in testing; re-encoding the same five seconds from six seconds in took 1.2 seconds. If you only need the end gone, leaving the start at zero is close to free.

Landing on the right moment

The handles move in hundredths of a second and the preview seeks to whichever one you last touched, so you see the frame you are cutting on rather than guessing from a waveform or a timeline. The timecodes above them say where both are.

A cut that re-encodes is frame accurate: it starts on exactly the frame you chose. A copied cut lands on the nearest key frame instead, which can be up to a second or two out, because a frame in the middle of a chain cannot begin a file. That is the trade for losing nothing, and it is the same trade every editor makes.

Keeping the quality

Matching the original aims the encoder at the bitrate the source file was already using, worked out from its size and its length. That is as close as a re-encode gets, and on ordinary footage the difference is not visible.

The smaller setting is there when the point of the trim is a file you can send. A 10 second clip out of a phone video is about 21 MB at the original bitrate and under 5 at the smaller setting, which is usually the difference between attaching it and not.

Limits

500 MB per file.
The result is an MP4. The original container is not preserved.
A copied cut starts at the nearest key frame, which can be a second or two before the handle.
One section per run. Removing a piece from the middle means two trims and joining them elsewhere.

Frequently asked questions

Does trimming reduce the quality?: Not if the cut starts at the beginning, because the frames are copied rather than encoded again. Starting partway in requires a re-encode, and the quality setting then decides how close to the original it stays.
Why did my clip start slightly before the handle?: A copied cut has to begin on a key frame, and those are a second or two apart. Choosing a quality instead of matching the original makes the cut frame accurate, at the cost of re-encoding.
Can I cut a piece out of the middle?: Not in one go. Trim the part before it and the part after it, then join them in an editor. This tool keeps one continuous section.
Is the sound trimmed too?: Yes, to the same range, and it stays in step with the picture. You can also remove it entirely, which is worth doing when the clip is going somewhere that plays muted anyway.