Aspect ratio calculator
Enter the width and height of your image or screen. The ratio and the resize boxes update as you type.
What you enter stays on this page and is not sent anywhere.
Common ratios
- Aspect ratio
- 16:9
- Width divided by height
- 1.778
- Height divided by width
- 0.563
How to use it
- Enter the width and height, or tap a common ratio.
- Read the simplified ratio and the decimal value.
- To resize, type a new width or a new height. The other side fills in.
Questions
How is the ratio worked out?
Width and height are divided by their greatest common divisor. For 1920 by 1080 that divisor is 120, which leaves 16:9.
Why does 1366 by 768 show 683:384?
That is its exact ratio. It is within half a percent of 16:9, so the tool names 16:9 as the nearest common ratio.
How is the new size calculated?
New height = new width times height divided by width, and the other way round. Results are rounded to two decimals, so round to whole pixels yourself.
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