Resize video
Scale a clip to a width, keeping aspect or forcing a size.
This runs in your browser. Nothing is uploaded. Longer clips take longer here than they would on a fast server — that is the trade-off for not sending the file.
About Resize video
Scales a video to a new width in your browser with FFmpeg’s scale filter, optionally locking aspect ratio, with no upload.
Phone clips at 4K are a nuisance in a slide deck. This page re-encodes at the width you type. Keep aspect ratio (the default) sets height to an even number FFmpeg will accept (`-2`). Uncheck it and you can squash the frame on purpose, which looks awful and is occasionally what a form field demands.
Width and height should be even. The page rounds to even numbers because H.264 and VP8 are fussy. You will not get a 1277-pixel-wide file, and that is fine. This is not a crop tool with a box you drag — crop lives conceptually next door but on this pass the control is scale only.
Re-encoding means you pay quality. If you only needed a smaller file, try Compress first. If you needed a 1080p export from a 4K source for a site that caps resolution, this is the control.
Social presets (9:16, 1:1) are not on this page. Type the pixel width you actually need rather than hoping a named preset matches the site you are posting to.
How to use Resize video
- 1Drop the clip.
- 2Set width (and height if you are not keeping aspect).
- 3Click Resize, then Download.
What it won't do
- Scale only, no crop UI.
- Always re-encodes.
Common questions
Is this a crop tool?
No. It scales the whole frame. Pillarboxing or cutting a centre region is a crop, which I have not shipped as its own video page yet. Do not type a width and expect the sides to fall off.
Why is height disabled when aspect is locked?
Because height is then derived. Type width. FFmpeg gets `scale=W:-2` so the other dimension stays even and proportional.
Will upscaling look sharp?
No. You cannot invent detail. Upscaling a 480p clip to 1920 wide makes a soft 1920-wide clip. Use this to go down, mostly.
Related tools
Why this one doesn't upload your file
There is no server to upload to. This page is a static file, and the work happens in your browser using the same graphics and WebAssembly code that renders every other site you visit. Your file is read from disk into memory, processed, and handed back as a download. Once the page has loaded you can disconnect from the network entirely and it keeps working. The longer explanation