Instantly calculate the aspect ratio of any dimensions or find equivalent pixel sizes for a given ratio. Works in both directions: dimensions to ratio, or ratio to dimensions.
Open Aspect Ratio Calculator → free, no sign-inAspect ratios come up constantly in design and development: you have an image at 1920×1080 and need to know what height to use at 800px wide. Or you're designing for a 16:9 canvas and need the exact pixel dimensions. The Aspect Ratio Calculator does both directions: enter any width and height to get the ratio, or enter a ratio and one dimension to get the other. It also outputs a range of equivalent common sizes.
Web developers sizing responsive images, video editors setting canvas dimensions, designers checking that an asset maintains its proportions — anyone who regularly needs to work out equivalent dimensions will find this genuinely useful.
No tutorials. No learning curve. Open it and get started.
No server uploads. Calculates the greatest common divisor to express the ratio in its simplest form — so 1920×1080 gives you 16:9, not 192:108.
Completely free. No trial period. No premium tier for basic functionality. No account required. Use it as often as you need.
One job, done well. Aspect Ratio Calculator was built to solve a specific problem cleanly. No feature bloat, no ads, no distractions.
What is an aspect ratio?
An aspect ratio describes the proportional relationship between width and height, expressed as two numbers separated by a colon — for example 16:9.
How is the ratio simplified?
The tool divides both numbers by their greatest common divisor to express the ratio in its simplest form.
Can I use decimal dimensions?
Yes — the calculator handles decimal input values.
What's the difference between 16:9 and 1.78?
They represent the same ratio — 16÷9 = 1.77̄. The colon notation is used in display contexts; the decimal in some technical specifications.
Does it handle portrait orientation?
Yes — enter height greater than width for portrait ratios.
Free. Instant. No sign-in. Open it and get the job done.
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