What is aspect ratio?

Aspect ratio is the proportional relationship between width and height. It is usually written as width:height, such as 16:9 or 4:3.

How do I calculate aspect ratio from width and height?

Divide width by height to get the decimal ratio, then reduce both numbers by their greatest common divisor to get the simplified ratio.

What is the most common aspect ratio?

16:9 is the most common modern ratio for video, laptops, TVs, presentation decks, and web embeds.

What aspect ratio is 1920x1080?

1920 x 1080 simplifies to 16:9, the standard widescreen video format.

How do I maintain aspect ratio when resizing?

Keep one side fixed and calculate the other side from the ratio. If the width changes, multiply it by height divided by width from the original ratio.

What aspect ratio should I use for YouTube videos?

Use 16:9 for standard YouTube videos. Shorts and mobile-first vertical video use 9:16.

What is the difference between 16:9 and 4:3?

16:9 is wider and better for modern displays. 4:3 is more compact and still appears in slides, retro content, and certain camera outputs.

How do I calculate aspect ratio in CSS?

Use the modern `aspect-ratio` property or the classic padding-top technique, where padding-top equals height divided by width times 100%.

◫Aspect RatioCalculator

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Aspect Ratio Calculator

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