What is an aspect ratio?

An aspect ratio is the proportional relationship between the width and height of an image or screen (e.g., 16:9).

How do I calculate a new dimension?

Enter your current width and height, then enter the target width or height to see the corresponding dimension calculated automatically.

Are there common presets?

Yes, we include presets for popular ratios like 16:9 (HD), 4:3 (SD), 1:1 (Square), and more.

Yes, it's 100% free and works entirely in your browser.

Free Online Aspect Ratio Calculator & Image Dimension Tool

Calculate image aspect ratios

Verified Local Processing (100% Client-Side)

Your data never touches our servers. All logic executes in your browser sandbox using WebAssembly (WASM). No uploads, no logging, zero data retention.

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Aspect Ratio Calculator

Calculate the aspect ratio of images and videos

Width (px)

Height (px)

About Aspect Ratio

Calculate image aspect ratios online for free. Find the perfect width and height for any ratio. Essential tool for video and design.

Key Features

Calculate dimensions from ratios like 16:9, 4:3
Inverse calculation (Ratio from dimensions)
Presets for popular social media platforms
Simple and accurate math for designers

How to Use

1Enter your known width or height
2Select a target aspect ratio preset
3Immediately see the resulting dimension calculated

Frequently Asked Questions

Everything you need to know about Aspect Ratio Calculator.