Aspect Ratio Calculator

Calculate width, height and aspect ratios (16:9, 4:3…).

Edit width to auto-calc height, or vice versa.

About this tool

The Aspect Ratio Calculator helps you resize videos, images and screens while keeping the correct proportions. Enter a known width or height and a target ratio (like 16:9, 4:3 or 1:1), and it computes the matching dimension instantly. It is essential for video editors, designers and developers preparing content for YouTube, Instagram, TikTok and websites without distortion.

How to use

  1. 1Pick a ratio or enter a custom one.
  2. 2Type a known width or height.
  3. 3Read the calculated dimension.

Benefits

  • Common presets (16:9, 4:3, 1:1, 21:9).
  • Custom ratios supported.
  • Instant, no distortion.

Frequently asked questions

What is 16:9?+

It is the standard widescreen ratio used by YouTube and most modern videos and screens.

Can I use a custom ratio?+

Yes. Enter any width:height ratio and the tool keeps your dimensions proportional.

Share this tool:X / TwitterFacebook