Aspect Ratio Calculator

Compute, simplify and scale aspect ratios for video and images.

How to use this tool

  • Enter width and height (or a ratio like 16:9).
  • Choose to simplify, scale to a new width/height, or compare.
  • Read the result.

How it works

GCD simplifies a width/height pair to lowest terms; scaling multiplies the ratio to hit a target dimension.

Tips

  • Before crop, decide the deliverable ratio — social media wants 4:5, cover art 1:1, YouTube 16:9.
  • Scaling preserves the ratio, so no distortion.

Limitations

Non-standard ratios (odd numbers) simply stay as-is.

Frequently asked questions

How do I get 16:9 from 1920x1080?

Divide width and height by their greatest common divisor (1920/120=16, 1080/120=9). The tool does this.

How do I scale a ratio to a width?

Height = width / (ratioW/ratioH). To keep 16:9 at 1280 wide, height = 720.

Can I compare two dimensions?

Enter two sizes and the tool reports whether they share the same ratio.