Resize images

Resize changes an image's pixel dimensions in your browser — set a width, a height, or both, or scale by a percentage between 1% and 200%. Downscaling by more than half is done as a series of halving draws rather than one, which keeps a big reduction from coming out aliased and crunchy. Upscaling is switched off by default, so the output is never enlarged past the original unless you ask for it.

How it works

  1. Add your images Drop one or more files onto the page. Each row shows the source dimensions, so you can see what you are scaling from.
  2. Choose pixels or percent Pixels takes a width and a height, with preset widths of 1280, 1920, 2560 and 3840. Percent replaces them with a single scale slider from 1 to 200.
  3. Pick a fit Contain fits the image inside the box and keeps the aspect ratio. Cover fills the box and crops the overflow from the centre. Stretch takes the exact box and ignores the ratio.
  4. Decide about upscaling Leave "Allow upscaling" off to cap the result at the original size, or turn it on if you deliberately want a larger canvas.
  5. Process and download Press process, then download. One file saves directly; a batch comes back as a zip.

Questions

Does resizing keep the aspect ratio?
With the default contain fit, yes: leave either width or height empty and the missing side is worked out from the original proportions. Cover keeps the ratio too but crops the overflow from the centre, and stretch is the one mode that deliberately distorts the image to hit an exact box.
Can I control the compression quality of the resized file?
Not in this tool. Resize writes lossy output at a fixed quality of 0.90 and offers only Keep, WebP, PNG and JPEG as formats. If you need to choose a quality or hit a file size, resize first and then use the compress tool.
Why does it refuse to enlarge my image?
Enlarging past the original adds pixels but not detail, so "Allow upscaling" is off by default and the requested box is shrunk proportionally to fit the source. Turn the toggle on and the exact dimensions you typed are used.

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