VideoLosslessRuns in your browser

Trim Video

Keep just the section you need by start and end timestamp. The conversion is lossless — every pixel, sample or byte in the source is preserved.

Not uploaded to any serverConverted on this deviceGone when you close the tabHow this works

Drop your files here

MP4, MOV, MKV, WebM and 2 more formats · up to 512 MB each

or paste files from your clipboard

Ready when you are

Keep just the section you need by start and end timestamp. Everything happens in this tab; nothing is sent anywhere.

⌘K to search converters

How to use it

1
Add your files
Trim Video works with MP4, MOV, MKV, WebM, AVI and TS. Drop them in, browse for them, or paste from your clipboard.
2
Choose your options
Tune codec, resolution and bitrate and start and end times — or leave the defaults, which are sensible.
3
Run it and download
Press the button and save the result. Everything happens on your device, and nothing is uploaded.

Privacy, in plain words

Is it safe? Your video file is not uploaded anywhere

What “uploaded” normally means. On most online converters, pressing the button copies your file across the internet onto a computer owned by that website. That copy is what the word “upload” means, and it is the part nobody explains.

What happens instead. This site does not do it. There is no server here that receives files, so your video file is read, converted and handed back by the browser you are using right now. It never travels — so there is no copy to store, read, leak or hand over.

Check it yourself in ten seconds

Turn off your Wi-Fi after this page has loaded, then convert a file anyway. It still works, because everything needed is already on your device.

The longer explanation of how this works, and the full detail of what is and is not stored on the privacy page.

Why this matters more than it sounds

Video is the format where the thing being converted is usually a recording of people, and often of people who did not expect a third party to have a copy. It matters more than it sounds, because of what video files usually are:

Family videos

children, addresses, the inside of your house

Medical or therapy consultations

clinical recordings under strict handling rules

Unreleased footage

material under embargo or still being edited

Recorded meetings and calls

everything said, by everyone in the room

A file that is never sent cannot be kept, leaked, subpoenaed or used to train anything. That is a property of how this works, not a promise about how carefully it is run.

How Trim Video works

Keep just the section you need by start and end timestamp. Everything happens inside this page: the file is read from your device into memory, processed there, and handed back as a download. It is never sent anywhere, and closing the tab discards it.

What it accepts: MP4, MOV, MKV, WebM, AVI, TS. Files are identified by their contents rather than their name, so a mislabelled file is still handled correctly.
What happens to the data: Nothing is re-encoded. The content that comes out is identical to the content that went in, byte for byte, and running it twice changes nothing.
Size limit: Up to 512 MB per file. Because the work happens on your own machine, available memory is the real constraint — a laptop handles far more than a phone.

The settings, and what each one changes

Trim Video exposes 8 settings. The defaults are chosen to suit the common case, so changing nothing is a reasonable way to start.

Start at: Leave both empty to keep the whole file. Accepts seconds or HH:MM:SS.
End at: Free text, used exactly as you type it.
Target: Free text, used exactly as you type it.
Resolution: Choose between Keep original, 4K — 2160p, QHD — 1440p, Full HD — 1080p and others.
Frame rate: Choose between Keep original, 60 fps, 30 fps, 24 fps and others.
CRF: Constant Rate Factor. Lower is better quality. 18–28 is the useful range.
Encoder speed: Choose between Ultrafast, Very fast, Medium, Slow.

Worth knowing before you start

With “Remux only” selected the cut is lossless but snaps to the nearest keyframe. Pick any other preset for a frame-accurate cut with a re-encode.

Measured, not estimated

What this tool actually does to a file

Keeping the first second of a two-second clip.

The result came out 2.0× smaller than the file that went in.

Each row is one document, chosen because this tool behaves differently depending on what is inside the file.
Sample	In	Out	Change
An easy clipThe compressible end of the range — a clean tone, or a moving test pattern — where a codec does its best work.	70.9 KB	36.5 KB	−48%
A hard clipThe other end — pink noise, or dense video grain. Close to incompressible by design, and the worst case for every codec.	1000 KB	509 KB	−49%

Produced by this site's own converter. The same code that runs in your browser, at the same default settings, so these are the bytes you would download.

Samples are generated from a fixed seed rather than taken from real photographs or documents, so the corpus is reproducible and carries no licensing question — and so the numbers predict the shape of your result rather than its exact size. Measured 2026-10-01. The method, and the command that regenerates every figure on this page, are on the how it works page.

About these formats

Accepts

MPEG-4 Part 14

The default video container of the internet.

Extensions: .mp4, .m4v
MIME type: video/mp4
Best for: Sharing anywhere · Streaming · Social media
Compatibility: Plays on effectively every device.

Accepts

QuickTime Movie

Apple's QuickTime container, common from iPhones and cameras.

Extensions: .mov, .qt
MIME type: video/quicktime
Best for: Apple ecosystem · Video editing
Compatibility: Excellent on Apple, patchy on Windows and Android.

With “Remux only” selected the cut is lossless but snaps to the nearest keyframe. Pick any other preset for a frame-accurate cut with a re-encode.

Good to know

Trim Video — questions

How does Trim Video work?

Keep just the section you need by start and end timestamp. Add your files above, adjust anything you want to change, and press the button. The result downloads straight to your device.

Is there anything I should watch out for?

With “Remux only” selected the cut is lossless but snaps to the nearest keyframe. Pick any other preset for a frame-accurate cut with a re-encode.

Is Trim Video safe — are my files uploaded to a server?

No, nothing is uploaded. On most online tools, pressing the button copies your file across the internet onto a computer owned by that website, where it is processed and then sent back. That copy is what "upload" means. This tool does not do it: your file is read and processed by the browser you are using right now, stays on this device the whole time, and is discarded when you close the tab. Turn off your Wi-Fi after the page loads and it still works, which is the quickest way to confirm it.

Can I use this on confidential or personal documents?

Yes — that is the case it was built for. Because the file never leaves your device, a confidential document is no more exposed than it is sitting in your own folder: there is no transfer, no copy on anybody else's hardware, no retention period and no staff with access. Nothing about the file is logged either — not its name, not its size, not its contents.