What is an aspect ratio?

An aspect ratio is the proportional relationship between the width and height of an image or screen. It is expressed as two numbers separated by a colon, such as 16:9.

How is the simplified ratio calculated?

The tool finds the greatest common divisor (GCD) of the width and height, then divides both by it to produce the simplest whole-number ratio.

Can I calculate missing dimensions?

Yes. Enter a known width or height along with a ratio, and the tool will calculate the missing dimension while maintaining the aspect ratio.

What are common aspect ratios?

Common ratios include 16:9 (widescreen/HD), 4:3 (classic TV), 1:1 (square), 21:9 (ultra-wide), and 3:2 (photography). The tool provides presets for all of these.

Aspect Ratio Calculator

Calculate aspect ratios, simplify ratios, and resize dimensions proportionally.

Find Aspect Ratio

Width

Height

Aspect Ratio

16:9

Calculate Dimensions from Ratio

Ratio W

Ratio H

Enter Width

Calculated Height

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Enter Height

Calculated Width

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How to Use Aspect Ratio Calculator

Step 1

Enter width and height to see the simplified aspect ratio.

Step 2

Or select a common preset ratio (16:9, 4:3, etc.).

Step 3

Enter a target width or height to calculate the other dimension.

Step 4

Results update in real time as you type.

Features

Simplifies any width:height to the smallest whole-number ratio.

Calculate missing dimensions from a known ratio.

Common presets: 16:9, 4:3, 1:1, 21:9, 3:2.

Real-time calculations as you type.

Completely client-side — no data sent to any server.

FAQ

: An aspect ratio is the proportional relationship between the width and height of an image or screen. It is expressed as two numbers separated by a colon, such as 16:9.
: The tool finds the greatest common divisor (GCD) of the width and height, then divides both by it to produce the simplest whole-number ratio.
: Yes. Enter a known width or height along with a ratio, and the tool will calculate the missing dimension while maintaining the aspect ratio.
: Common ratios include 16:9 (widescreen/HD), 4:3 (classic TV), 1:1 (square), 21:9 (ultra-wide), and 3:2 (photography). The tool provides presets for all of these.