Skip to content
browserutils

Aspect Ratio Calculator

Calculate and lock aspect ratios for width and height

Aspect Ratio Calculator is a free online tool from BrowserUtils that calculate and lock aspect ratios for width and height. It runs entirely in your browser — your data never leaves your device. No account required.

16:9
1.7778

How to use Aspect Ratio Calculator

  1. 1 Paste or type your input into the editor above.
  2. 2 The tool processes your data instantly — right in your browser, with nothing sent to a server.
  3. 3 Copy the result with one click or continue editing your input.

About Aspect Ratio Calculator

Free online aspect ratio calculator. Calculate aspect ratios, resize dimensions proportionally, and find equivalent widths and heights. This tool runs entirely in your browser — your data is never sent to a server. Just paste your input, get instant results, and copy with one click. No sign-up or installation required.

Aspect Ratio Calculator specs

Runtime
100% client-side (browser)
Cost
Free — no account, no rate limits, no usage caps
Browser support
Chrome 90+, Firefox 88+, Safari 14+, Edge 90+
Part of
299 developer tools on BrowserUtils (100% client-side)

Questions

What is an aspect ratio?
An aspect ratio is the proportional relationship between width and height, expressed as W:H. Common ratios include 16:9 (widescreen), 4:3 (standard), and 1:1 (square).
How do I maintain aspect ratio when resizing?
Lock the ratio, then change either width or height. The other dimension is automatically calculated to preserve the original proportions.
What aspect ratio should I use for social media images?
Instagram posts use 1:1 (square) or 4:5, Instagram Stories use 9:16, YouTube thumbnails use 16:9, and Facebook shared images work best at 1.91:1. This calculator helps you find the exact pixel dimensions for any ratio.
How do I find the aspect ratio of an image I already have?
Enter the width and height in pixels and the tool will reduce them to the simplest ratio. For example, 1920x1080 simplifies to 16:9.
Does this aspect ratio calculator work offline?
Yes. All calculations run entirely in your browser with no server requests. Once the page has loaded, you can use it without an internet connection.
Embed this tool

Copy this code to embed the tool on your website. Adjust the height to fit your layout.

<iframe src="https://www.browserutils.dev/embed/aspect-ratio-calculator" width="100%" height="500" frameborder="0" title="Aspect Ratio Calculator"></iframe>

Related tools

More Math & Calculators

View all Math & Calculators tools