How to resize an image without stretching
To preserve an image's shape, multiply both dimensions by the same scale factor. If a 2400 × 1600 image is resized to 1200 pixels wide, the scale factor is 0.5 and the new height is 800 pixels.
Formula
When resizing by height, calculate the width as original width × new height ÷ original height. The calculator rounds to the nearest whole pixel, so the displayed ratio may differ by a tiny amount for dimensions that do not divide evenly.
Resize versus crop
Resizing changes pixel dimensions while keeping the same shape. Cropping removes part of the image to fit a different shape. If you need a square thumbnail from a wide image, use a crop tool rather than forcing the width and height independently. See crop vs resize and the image aspect ratio checker.
Frequently asked questions
Will resizing make a small image sharper?
Increasing pixel dimensions does not recover original detail. Upscaling can soften an image; use a good resampling method and start with the highest-quality source available.
What does preserving aspect ratio mean?
It means width and height change by the same scale factor, so circles stay circular and people do not look stretched.
Should I resize or crop for social media?
Resize if the destination supports the same shape. Crop or reframe if the destination requires a different aspect ratio.
Calculate the new dimensions before exporting.
Check an image's ratio