How to use this tool
Enter positive whole-number width and height values in the same units. Their greatest common divisor gives the reduced aspect ratio. Enter a new width to calculate the corresponding height without cropping. The tool also rounds that height to a whole pixel; rounding can slightly change the exact proportion.
Try these values
1920 × 1080 reduces to 16:9. At a new width of 1280, the proportional height is 720.
Common questions
Does this resize an image file?
No. It calculates dimensions; it does not upload, edit or export an image.
Can I enter centimetres instead of pixels?
Yes, if width and height use matching whole-number units. The ratio is unitless.
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