Image Resizer

When you pick an image, both boxes fill in with its current size. Keep aspect ratio is ticked by default: you type a width and the tool works out the height as width ÷ original width × original height, rounded to the nearest pixel. The height box is greyed out while the lock is on.

Untick the box to type both numbers yourself. The whole image is then stretched or squeezed to fit. Nothing is cropped and no borders are added, so a 4032 × 3024 photo forced to 1000 × 1000 will look squashed.

• PNG in, PNG out. Transparency is kept.
• JPG or WebP in, JPG out, saved at 92% quality. A WebP with a transparent background comes back with black where the transparency was, because JPG has no alpha channel and the tool doesn't paint a background first.

The file name gets the new size added, so holiday.jpg resized to 1200 wide downloads as holiday-1200x900.jpg.

The tool will happily scale up: an 800 × 600 image set to 1600 wide becomes 1600 × 1200. The browser fills in the extra pixels by smoothing between the existing ones, so the result is bigger but not more detailed, and edges look soft. If you need a large version, go back to the largest original you have.

There's no fixed maximum written into the tool's code. Very large outputs depend on how big a canvas your browser and device can handle, and the image is processed on your device rather than uploaded.

Resizing and compressing solve different problems. Resizing cuts the number of pixels; the Image Compressor keeps every pixel and lowers JPEG quality instead. For a phone photo going into an email or a form with an upload limit, resizing usually does most of the work: a 4032 × 3024 photo cut to 1200 × 900 has about 9% as many pixels. If it's still too big, run the resized file through the compressor.

For a web page, resize to the largest width the image is actually displayed at. Anything wider is downloaded by visitors and then thrown away by their browser.