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Trim MP4 Online

Trim MP4 files online — set a start and end point and keep just the part you need. Fast stream-copy trimming in your browser, with a re-encode fallback when frame accuracy matters.

The ten-second job that used to need an editor

Most MP4 trimming is not editing — it is amputation of dead air: the five seconds before the meeting actually starts, the tail of a screen recording, the middle where nothing happens. Opening a full video editor for that is overkill, and uploading a long recording to a web service is slow and unprivate. The trim video tool above does the cut in your browser: give it a start and an end, take the clip.

Stream copy first, precision when asked

The fast path is stream copy: the segment between keyframes is lifted out untouched — no re-encode, no quality loss, done in seconds. Its one constraint is granularity, since cuts land on keyframes. When the tool detects that your requested start falls between keyframes and accuracy matters, it re-encodes just that segment. You get speed by default and precision when it counts, which is the right trade for a quick-trim page. For the format-neutral version see trim video online, or the video trimmer overview.

Trim, then shrink

A trimmed clip is often still too big to send. After cutting, the natural next step is the compressor — remove the footage you do not need first, and the file you then compress starts smaller and finishes faster.

Private by design

Your MP4 never leaves the device. Recordings are trimmed locally, with no upload queue and no watermark — the way a quick utility should behave.

Frequently asked questions

Does trimming an MP4 reduce its quality?

With stream copy, no: the kept segment is copied bit-for-bit without re-encoding, so quality is identical and the trim is nearly instant. Frame-exact cuts may need a re-encode, which the tool falls back to automatically.

Why might my cut start a fraction early?

Stream copy can only cut at keyframes — the fully stored frames in the video — so the start may snap to the nearest keyframe. If the exact frame matters, let the tool re-encode the segment for precision.

What is the maximum MP4 size?

Limits are shown on the tool. Because trimming happens in your browser's memory, very large files (multi-GB recordings) are better trimmed in a desktop editor; typical clips and screen recordings are fine.

Can I trim other formats too?

Yes — the same trimmer accepts MOV, WebM and MKV. This page focuses on MP4 because it is the most common case; the general video trimmer page covers all formats.

Is my video uploaded?

No. The MP4 is read, cut and saved entirely in your browser. Nothing is sent to a server, and no watermark is added.

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