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Video Trimmer

Cut a section out of a video by start time and duration, without re-encoding it.

Video Trimmer

Trim videos directly in your browser.

What Video Trimmer does

Trimming removes the parts of a clip you do not want. This tool copies the existing video and audio streams rather than re-encoding them, which makes it fast and keeps the original quality exactly.

The trade-off is precision. Because the streams are copied, cuts can only land on keyframes, so the actual start point moves to the nearest one — typically within a second or two.

  • Set a start time and a duration
  • Stream copy, so no quality is lost
  • Progress shown while processing

How to use Video Trimmer

  1. 1

    Add your video

    The FFmpeg engine downloads when you start your first operation, which takes a moment.

  2. 2

    Set the start time

    Enter it as hours, minutes and seconds.

  3. 3

    Set the duration

    Enter how many seconds to keep from that point.

  4. 4

    Trim and download

    Check the result, since the cut may have moved to a nearby keyframe.

Limits and known behaviour

  • Cuts land on keyframes, so the start can be up to a couple of seconds away from what you asked for. Frame-accurate trimming requires re-encoding, which this tool does not do.
  • There is no timeline scrubber; times are typed rather than selected visually.
  • Output is MP4. Copying streams from another container, such as a VP9 WebM file, into MP4 can fail because MP4 does not accept every codec.
  • Only one section can be removed per pass.
  • Large files are limited by memory, since the whole video is held in the page.
  • The first operation downloads roughly 30 MB before anything can start.

Privacy and data handling

Runs in your browser after a one-time download

  • Your media file is not uploaded. It is processed in this page.
  • To do that, the FFmpeg engine — roughly 30 MB of WebAssembly — is downloaded from the public unpkg CDN when you start your first operation. That request reveals your IP address to the CDN and tells it which files you fetched. It does not carry your media.
  • After the engine loads, all processing happens on your own processor.
  • Nothing is retained after the tab is closed.

Site-wide data handling, including analytics and advertising, is described in the privacy policy.

Frequently asked questions

Why did my clip start a second early?

Because copying streams without re-encoding means cutting at a keyframe, and the nearest one may be slightly before your requested time. Precise cuts require re-encoding.

Why is the first run slow?

The FFmpeg WebAssembly build has to download and compile before any processing can begin. Later operations in the same session reuse it.

Why did my WebM file fail?

The output container is MP4, which cannot hold every codec. A VP9 or AV1 stream copied into MP4 will be rejected.