Aspect Ratio Calculator
Calculate aspect ratios from width and height. Resize dimensions proportionally with common presets and a visual preview.
Calculate Aspect Ratio
Visual Preview
Resize Calculator
About Aspect Ratio Calculator
This aspect ratio calculator helps you determine the ratio of any width and height, resize dimensions proportionally, and visualize the result. It is an essential tool for designers, video editors, photographers, and developers working with screens and images.
Calculate Any Ratio
Enter a width and height in pixels (or any unit) and the calculator instantly reduces them to the simplest aspect ratio. For example, entering 1920 and 1080 returns 16:9. The calculation uses the greatest common divisor to find the most reduced form.
Resize Calculator
Need to scale an image to a specific width while keeping the same proportions? The resize section lets you lock in an aspect ratio and enter one dimension to compute the other. This ensures your content is never stretched or distorted when changing sizes.
Common Presets
Quickly select from popular aspect ratios including 16:9, 4:3, 21:9, 1:1, 9:16, and 3:2. Each preset loads into the resize calculator so you can immediately start computing dimensions.
Visual Preview
A proportionally scaled rectangle updates in real time to show exactly what the current ratio looks like. This visual reference makes it easy to compare ratios at a glance and understand how different proportions affect layout.
Common Uses
- Resizing images for websites and social media platforms
- Setting up video project dimensions in editing software
- Designing responsive layouts that maintain proportions
- Choosing monitor or TV screen sizes
- Calculating print dimensions from digital files
All calculations run instantly in your browser with no data sent to any server.
Frequently Asked Questions
What is an aspect ratio?
An aspect ratio describes the proportional relationship between the width and height of an image, screen, or video. It is expressed as two numbers separated by a colon, such as 16:9 or 4:3. A 16:9 ratio means the width is 16 units for every 9 units of height.
How does the resize calculator work?
Select or enter an aspect ratio, then type either a width or height value. The calculator automatically computes the missing dimension to maintain the exact ratio. This is useful when resizing images or videos to fit a specific width while preserving proportions.
What are the most common aspect ratios?
The most common aspect ratios are 16:9 (widescreen monitors and TVs), 4:3 (classic TV and presentations), 1:1 (square, common on social media), 21:9 (ultrawide monitors), 9:16 (vertical mobile video), and 3:2 (classic photography and some laptops).
Why does the calculator simplify my ratio?
The calculator reduces your width and height to the simplest whole-number ratio using the greatest common divisor. For example, 1920x1080 simplifies to 16:9 because both dimensions share a common factor of 120. The simplified form is easier to recognize and compare.