UseTool

Video editor

Trim, crop, rotate, adjust colours, change speed and sound, and add text in one local editor.

🔒 Your videos never leave your device.

Drop your video hereMP4 · MOV · WebM

How it works

How it works

  1. 1

    Add what goes in

    Drop your MP4, MOV, M4V, WebM and MKV here, or pick it from your device.

  2. 2

    Start it

    Set Trim clip, Text watermark, Volume, then start. Everything runs in this browser — no upload, no queue, no account.

  3. 3

    Take the result

    The WebM is ready the moment the run finishes. Save it straight to your device.

What this tool does

What goes in
Reads MP4, MOV, M4V, WebM and MKV. One file at a time.
What comes out
You get WebM.
What happens to quality
Every frame is decoded and encoded again. That is what makes the file smaller or different — and it costs some detail, most visibly in fast motion and fine texture.
Where it stops
Which video codecs work depends on your browser. Chrome and Edge read the most, including H.265 on many machines; Safari and Firefox refuse some. A file that will not open here usually opens in Chrome. A long or high-resolution video is limited by your device's memory. Phones give up earlier than laptops — half an hour of 4K can be too much.
Video editor
Trim, crop, rotate, adjust colours, change speed and sound, and add text in one local editor.

Supported formats

MP4MOVWebM → WebM

Good to know

Frequently asked questions

What files can I use here?

Reads MP4, MOV, M4V, WebM and MKV. One file at a time.

What do I get back?

You get WebM.

Does the file lose quality?

Every frame is decoded and encoded again. That is what makes the file smaller or different — and it costs some detail, most visibly in fast motion and fine texture.

When does it not work?

Which video codecs work depends on your browser. Chrome and Edge read the most, including H.265 on many machines; Safari and Firefox refuse some. A file that will not open here usually opens in Chrome. A long or high-resolution video is limited by your device's memory. Phones give up earlier than laptops — half an hour of 4K can be too much.

Does the video lose quality?

Only when it has to be re-encoded. Cutting, joining and removing the sound track copy the picture data unchanged, so those are lossless. Compressing and adding a watermark do re-encode, which is why they take longer.

How long may a video be?

There is no fixed limit. What decides is the memory of your device: a phone manages a few minutes comfortably, a computer handles far more. If a long video fails, splitting it first and working on the parts usually helps.

Private by design

Your files stay on your device

Your videos never leave your device.

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Ready-made

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