How to Use Aspect Ratio Calculator
Find the aspect ratio of any width and height, and calculate a new height (or width) that keeps the exact ratio — ideal for images, video and responsive design. Includes presets like 16:9, 4:3 and 1:1.
Open the Aspect Ratio Calculator tool →What is Aspect Ratio Calculator?
Resize dimensions while keeping the aspect ratio, with common presets. It's completely free, needs no sign-up, and runs entirely in your browser — so it's fast and private.
How to use Aspect Ratio Calculator
- Open the Aspect Ratio Calculator tool.
- Paste or type your input.
- Set any options provided.
- Copy the result. Everything runs in your browser — nothing is uploaded.
Frequently asked questions
How does it keep the ratio?
It works out the ratio of your original width and height, then scales the new dimension by the same factor so the proportions stay identical.
What are the presets for?
Quick access to common ratios like 16:9, 4:3, 1:1 and 9:16 for video, photos and social posts.
Does it simplify the ratio?
Yes — it reduces the width:height to its simplest whole-number form using the greatest common divisor.
Ready to try it?
Open Aspect Ratio Calculator →