Calculate Ratios for Responsive Design

Find the correct height for responsive images and containers given a fixed width and target ratio.

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Width (px)

Height (px)

Simplified ratio16:9

Decimal ratio1.7778:1

Named ratio16:9

Megapixels2.07 MP

16:9

Common dimensions

Responsive tips

📱

Responsive containers need a known aspect ratio to maintain layout. Enter your container width and ratio to get the exact height needed.

💡

The CSS padding-top trick: padding-top: 56.25% gives a 16:9 container. Calculate your ratio as (h/w × 100)% to get the right percentage.

🖥️

Modern CSS: aspect-ratio: 16/9 works in all modern browsers. Use the simplified ratio output from this tool directly in CSS.

📐

For <img> tags, always specify width and height attributes matching the image's natural ratio. Prevents layout shift (CLS) as images load.

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Proses

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