Work out aspect ratios in seconds. Simplify a width and height to its simplest ratio, or find a missing dimension that keeps the same proportions — handy for resizing images, video and screens. Free, instant and private, with no sign-up needed.
Simplify a ratio
Find a missing dimension
How to Use
- To simplify: enter a width and height, then click Simplify Ratio.
- To resize proportionally: enter the ratio, choose the side you know, enter its value, then click Find Missing Side.
Key Features
- Ratio simplification – 1920 × 1080 becomes 16:9 instantly.
- Missing dimensions – resize images or video without distortion.
- Decimal friendly – missing sides are rounded to two decimals.
- 100% private – everything runs in your browser; nothing is sent anywhere.
FAQs
Is this aspect ratio calculator free?
Yes. It is completely free with no sign-up and no limits.
What is an aspect ratio?
An aspect ratio describes the proportional relationship between width and height. A 16:9 ratio means the width is 16 units for every 9 units of height — the standard shape of modern video.
How do I resize an image without stretching it?
Keep the same aspect ratio. Enter the image’s current ratio in the missing-dimension section, then enter the new width or height to find the matching side.
Is my data stored anywhere?
No. The calculation runs entirely in your browser and nothing is transmitted or saved.
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