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Geometry

Resize an image in pixels

Type the dimensions you need. The aspect ratio stays locked unless you say otherwise, and the second field updates as you type the first.

Drop a file here or click to browse — any image your browser can open

Result

Resized image

Enlarging is not the same as shrinking

Shrinking an image is safe. There is more information in the source than the destination can hold, so the browser averages neighbouring pixels together and the result is clean. This tool does the reduction in two steps when the shrink is severe, because a single large jump makes fine detail flicker away rather than blur gracefully.

Enlarging is a different matter. There is nothing to draw on but the pixels already present, so the extra ones are invented by interpolation and the picture gets softer in proportion to how far you push it. Going up by 20% is barely noticeable. Doubling is visible. Quadrupling looks like a painting. No browser-based tool can do better, because the detail simply is not in the file.

Choosing an output format

  • PNG for screenshots, logos, diagrams and anything with transparency. Lossless, so resizing costs you nothing beyond the resampling itself.
  • JPEG for photographs, when file size matters more than perfection.
  • WebP when the destination is a web page and you control the markup.

Common questions

How do I resize without stretching the image?

Leave the aspect ratio locked and fill in only one of the two fields. The other is calculated for you. If you need an exact width and an exact height that do not match the original proportions, unlock the ratio and the image will stretch, or better, use crop to cut it to the right shape first.

Does resizing reduce the file size?

Usually a great deal, because file size scales roughly with pixel count. Halving both dimensions quarters the number of pixels. If you have a specific byte target in mind, the compress to a size tools handle the arithmetic for you.

What happened to my transparent background?

If you saved as JPEG, it became white, because JPEG has no transparency. Choose PNG or WebP to keep it.

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