Aspect Ratio Calculator

Reduce width and height to the simplest aspect ratio like 16:9, with the decimal ratio. Fast and private.

Independently verified for accuracy

Calculator by Toolsloft ↗
Aspect ratio
16:9
Decimal ratio
1.78

Reduce a pixel width and height to their simplest aspect ratio, such as 1920 by 1080 to 16:9. Enter the two dimensions to get the whole-number ratio and the decimal width-to-height figure. Useful for video, images, and screen layouts.

How this is calculated

The width and height are divided by their greatest common divisor to get the smallest whole-number ratio. The decimal value is the width divided by the height, rounded to two places. Inputs must be positive whole numbers of pixels.

How to use

  1. Enter the width in pixels.
  2. Enter the height in pixels.
  3. Read the simplified ratio and the decimal value.

Examples

  • Widescreen: 1920 by 1080 reduces to 16:9
  • Classic: 640 by 480 reduces to 4:3

FAQ

How is the ratio simplified?
Both numbers are divided by their greatest common divisor, which gives the smallest pair of whole numbers with the same proportion.
What is the decimal value for?
It is the width divided by the height. A value near 1.78 is 16:9, and 1.33 is 4:3, which helps when a tool wants a single number.
Can I enter non-whole numbers?
No. Aspect ratios are reduced from whole pixel dimensions, so both width and height must be positive whole numbers.

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