OnlineConverTools
Sign In

Aspect Ratio Calculator

Calculate aspect ratios for any dimensions

16:9
Decimal: 1.7778

About Aspect Ratio Calculator

Aspect Ratio Calculator computes the simplified ratio and decimal value for any width and height you enter, live in your browser as you type. There's no output-format picker or dimension-scaling feature — it always shows both the ratio and the decimal value together.

How to use Aspect Ratio Calculator

  1. 1Type a width and height into the two fields.
  2. 2Read the simplified ratio (e.g. 16:9) and decimal value shown below.
  3. 3Click a preset button (16:9, 4:3, 1:1, 21:9, or 9:16) to instantly load common dimensions.
  4. 4Adjust width or height at any time — the ratio updates instantly.

Frequently Asked Questions

What is an aspect ratio?

The proportional relationship between an image's width and height, expressed as two numbers separated by a colon (e.g., 16:9).

Is Aspect Ratio Calculator free to use?

Yes, it's completely free with no signup required.

Can I choose between decimal, fractional, or ratio output?

No — both the simplified ratio and the decimal value are always shown together; there's no separate output-format selector.

Does it scale dimensions to match a target ratio?

No — it only simplifies whatever width and height you enter; it doesn't calculate a new width or height to match a target ratio.

Tips & Tricks

  • ✓Click a preset to quickly load common ratios like 16:9 or 1:1 instead of typing dimensions by hand.
  • ✓The decimal value (width ÷ height) is handy for CSS aspect-ratio properties.
  • ✓Non-numeric or empty inputs default to 1, so double-check a field if the result looks off.
  • ✓To find a height that matches a target ratio at a given width, try different height values until the ratio shown matches what you need.