Resize while keeping the same proportions
When you change one dimension of an image or video, the other must change in step or the result looks stretched. This calculator keeps the aspect ratio fixed: enter a new width and it gives the matching height, or the reverse. It's the quick way to resize to a target size without distorting the picture.
How to use it
- Enter the original width and height to set the ratio.
- Change either the new width or the new height.
- Read the matching dimension that keeps the proportions.
Common ratios
- 16:9 for most video and widescreen displays.
- 4:3 for older screens and some photos.
- 1:1 for square social images.
Questions people ask
Will resizing improve quality? No — scaling up can't add detail that isn't there. Keeping the ratio just prevents distortion.
Is my input stored? No — it runs in your browser.