Image guide
How to Resize an Image Without Distortion
Resizing changes pixel dimensions. Keep the original aspect ratio unless you intentionally want distortion, and choose dimensions based on where the image will be used.
Open the Image Resizer toolQuick answer
With aspect ratio locked, changing width recalculates height. A 2400 by 1600 image resized to 1200 pixels wide becomes 800 pixels high.
Dimensions, resolution, and ratio
Pixel width and height describe the digital image. Aspect ratio describes their proportion. Print resolution such as pixels per inch affects physical output calculations but does not add pixels.
Upscaling creates pixels by interpolation. It can make a file larger but cannot recover missing detail.
How to resize image files
- Find the maximum dimensions required by the destination.
- Upload the image and keep aspect ratio enabled.
- Enter width or percentage, process, and verify output dimensions.
Choose an output format and quality when offered, inspect the preview, then download a copy.
Calculate dimensions manually
Use new height = original height × new width ÷ original width. A 3000 by 2000 photo at 1500 pixels wide becomes 1000 pixels high.
A 50 percent resize produces one quarter of the original pixel count because both axes are halved.
Avoid soft or stretched results
Do not enter unrelated width and height values with aspect ratio unlocked unless stretching is desired. Crop to the target ratio first when a required frame would otherwise distort.
Export close to actual display size and keep the original for future sizes.
Try it in your browser
The free ToolPixels Image Resizer processes your file locally in the browser. Review the result and keep the original file.