WebAssetKit

Image tools

Resize Images by Pixels or Percentage

Set a new width and height in pixels, or scale by a percentage. The tool shows the exact output size before you download, and uses a multi-step downscale so reduced photos stay sharp instead of jagged.

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Drop an image here or click to choose · JPG, PNG, WebP, GIF, BMP, SVG · up to 25 MB · you can also paste

How to use the Image Resizer

  1. Add an image. The original size appears straight away.
  2. Choose “Pixels” or “Percent”. With the lock on, typing a width fills in the matching height (and the other way round).
  3. Pick the output format and quality, then press Resize.
  4. Compare with the original using the slider and download the result.

Tips for better results

  • Resizing down is safe; enlarging adds pixels but not detail, so large enlargements look soft. Tick “Do not enlarge” to prevent accidents.
  • For sharp, retina-ready web images, export at twice the display width (for example 1600 px for an 800 px wide slot).
  • Turn the lock off only when you really want to stretch the picture to an exact box; otherwise use the Social Media Image Resizer to crop to fit.

Limitations you should know about

  • The largest output side is 16,384 pixels, the most browsers can reliably handle. Mobile browsers may fail on very large images.
  • Resizing re-encodes the image, so JPG and WebP outputs lose a little quality and metadata is removed. Use PNG for a lossless result.
  • Animated images are reduced to their first frame.

Frequently asked questions

Will resizing reduce the file size?

Usually, yes. Fewer pixels means fewer bytes. For the smallest files, resize first, then run the result through the Image Compressor.

What does “lock aspect ratio” do?

It keeps the width-to-height proportions of the original so the picture is not squashed or stretched. If you enter both a width and a height, the image is fitted inside that box.

Is there a limit on the number of images?

This tool works on one image at a time so you can check the result. For a batch of web-ready files, the Image Compressor accepts up to 20 at once.

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