Aspect Ratio Finder

Find the aspect ratio

The aspect ratio of an image or screen is the proportional relationship between its width and height, written as two numbers such as sixteen-by-nine. This finder takes any width and height and reduces them to the simplest whole-number ratio by dividing both by their greatest common divisor. Nineteen-twenty by ten-eighty simplifies to sixteen-by-nine, the standard widescreen ratio. It also gives the decimal ratio and names the common ratio where it recognises one.

Reducing to lowest terms reveals the true shape regardless of the actual pixel dimensions.

Common aspect ratios

Different media use different standard ratios: sixteen-by-nine for widescreen video and most monitors, four-by-three for older displays and many photos, one-by-one for square social media posts, and nine-by-sixteen for vertical mobile video. Knowing the aspect ratio helps you choose the right crop, avoid letterboxing or distortion, and match content to the intended display.

Any width and height work, so you can find the ratio of a photo, a screen, a video or a design canvas. All calculation happens locally in your browser.

Notes

This Aspect Ratio Finder tool runs entirely in your browser, so nothing you enter is uploaded or stored on a server. The generated output is plain, standards-compliant code that you can copy, paste, edit and reuse freely in your own projects, documents and designs without any attribution or sign-up.

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