# Video trimmer: trim a video online, free, no upload

> Trim a video in your browser: set the start and end, by typing or from the player, and download the part you keep as an MP4. Exact or fast cut. Nothing is uploaded.

URL: https://cutfac.com/tools/video-trimmer  
Last updated: 2026-10-28  
Language: [한국어](https://cutfac.com/ko/tools/video-trimmer)

Drop in a video, set where the part you want starts and ends, and download it as an MP4. Times can come straight from the player, and the video never leaves your browser.

Runs in your browser. Nothing is uploaded.

## How to use it

1. **Add the video.** It loads into the player, with the end set to its full length.
2. **Set the start and end.** Type times like 1:23.5, or play to the spot and tap Use current time.
3. **Trim and download.** Play the piece to check it, then download the MP4.

## Exact cut or fast cut

Video is stored as key frames, full pictures, with the frames between them recorded as changes. A cut that starts between two key frames needs that frame rebuilt, so the exact cut encodes the piece again as H.264 at high quality. It starts where you set, and takes longer the longer the piece.

The fast cut copies the video as it is, so it's quick and loses nothing. Copying has to start on a key frame, so the file also carries the frames back to the key frame before your start, marked to be skipped. Browsers and most players start exactly where you set; a few editors ignore the mark and show that lead-in, and the file is larger.

## What you get

An MP4 with H.264 video and AAC sound that plays on phones, in browsers and in editors. This tool cuts time, not the picture: to cut off the edges of the frame, use the video cropper.

## With ffmpeg

FFmpeg's seeking guide explains the same trade-off. The first command copies, so it reaches back to a key frame; the second encodes and starts exactly:

- ffmpeg -ss 0:05 -to 0:12.5 -i input.mp4 -c copy clip.mp4
- ffmpeg -ss 0:05 -to 0:12.5 -i input.mp4 -c:v libx264 -crf 18 -c:a aac clip.mp4

## Sources

- [FFmpeg Wiki: Seeking](https://trac.ffmpeg.org/wiki/Seeking)

## Questions

### Is my video uploaded?

No. The video is read and the piece is written in your browser.

### Why is the fast cut's file bigger?

Copying has to begin on a key frame, so the file carries the frames back to the one before your start, marked to be skipped. Most players start where you set, but a few editors show that lead-in. Turn the fast cut off for a file that holds only your piece.

### Does trimming lower the quality?

The fast cut copies the video untouched. The exact cut encodes it again at high quality, which is close to the original but not identical.

### Can I cut out a part from the middle?

Not in one go: this tool keeps one stretch. Trim the two parts separately and join them in an editor.

### Which videos can it trim?

Whatever your browser can decode: MP4, MOV, WebM and most MKV files. The result is always an MP4.