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Free tool

Resize a video to exact pixels

Drop to 1080p or 720p, halve it, or type the width and height you were given. The aspect ratio locks by default, and unlocking it lets you letterbox, fill or stretch.

Your file never leaves this tab. It is read, edited and written by your own browser, so nothing is uploaded and nothing is stored.

Why this one

What this tool gets right

Presets and exact numbers

One tap for 2160p down to 360p, or 50 and 25 percent. Type both sides when a spec says 1080 by 1350 and nothing else will do.

Even dimensions, automatically

H.264 cannot represent an odd width, and several browsers refuse the encode rather than rounding. Every number here is nudged to an even one for you.

Three ways to fill a box

Unlock the ratio and choose: letterbox to keep everything, fill and cut to fill the frame, or stretch when you know that is what you want.

Smaller file as a side effect

Halving both sides quarters the pixel count. With the quality setting left alone, that is usually the fastest honest way to shrink a file.

How it works

Three steps, about thirty seconds

01

Drop the file in

Choose a file or drag it onto the page. It opens straight away, because there is nothing to upload.

02

Set it up

Drag the handles or type exact numbers. The preview applies the same operations in the same order the encoder will.

03

Export and download

Your machine does the encoding, with a real progress bar. The file lands in your downloads folder, unmarked.

Resolution, bitrate and what actually controls file size

Two things decide how big a video file is: how many pixels it has to describe, and how many bits it is allowed to spend describing them. Resolution sets the first, the quality setting sets the second, and neither on its own is 'compression'. Halving the width and height quarters the pixels, which usually cuts the file to roughly a third once the encoder has done its work. Dropping the quality one step at the same resolution can do as much with no visible change on a phone screen. Try the resolution first, because a smaller frame that is well encoded beats a large frame that is starved of bits.

Fit modes, in plain terms

Letterbox keeps the whole picture and pads whatever is left over, so nothing is lost and you get bars. Fill and cut scales until the box is covered and cuts the overflow, so the frame is full and the edges are gone. Stretch ignores the aspect ratio entirely and squashes the picture to fit. Stretch is almost never the right answer for footage of real people. It is occasionally the right answer for a graphic or a screen recording that was authored at the wrong ratio.

What this tool will not do

  • It will not fetch a video from YouTube, TikTok, Instagram or any other platform. You have to have the file.
  • It will not repair a corrupt or partially downloaded file. If a player cannot open it, neither can this.
  • It will not add anything to the picture: no captions, no logos, no filters. It edits the file you brought.
  • Speed is your hardware. A long 4K clip on a phone will take minutes where a laptop takes seconds.

Questions, answered

No. Scaling up invents pixels by interpolation; it cannot recover detail that was never recorded. It makes the file bigger and the picture softer. Upscale only when a platform rejects anything under a set size.
Leave the dimensions alone and lower the quality under Output, or switch the container to WebM, which uses more modern compression than an old MP4. Both re-encode, so check the result before you post it.
Because a re-encode does not know what bitrate your source used, and the quality preset may aim higher than the original did. Drop the quality a step, or resize to a smaller frame.
No. The file is opened by your browser with the File API and rewritten with WebCodecs, the same video machinery your browser uses to play a video. Nothing is sent to a server, so there is no upload wait, no queue and no copy of your file sitting in someone's storage bucket.
There is no limit we impose. The practical ceiling is your machine: the file is read in small pieces rather than loaded whole, so multi-gigabyte sources open instantly, and if you turn on 'write straight to disk' the result never has to fit in memory either. On a phone, expect long clips to be slow.
None of the three. Because the work happens on your machine, this costs us nothing to run, so there is nothing to gate. You get the file you made, unmarked.
Anything current: Chrome, Edge, Safari 17 and up, and Firefox 130 and up. The tools use WebCodecs, so a very old browser will report that it cannot encode, rather than producing a broken file.
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