Free tools for developers

Aspect Ratio Calculator

Calculate and scale dimensions while maintaining the aspect ratio. Scale width or height and get the missing dimension instantly.

Common Ratios

Find the Aspect Ratio

Width Height =

Scale by Width (keep ratio)

Ratio : New width
New height =

Scale by Height (keep ratio)

Ratio : New height
New width =

What is Aspect Ratio?

Aspect ratio is the proportional relationship between the width and height of an image, video, or screen. It is expressed as two numbers separated by a colon like 16:9. This means for every 16 units of width there are 9 units of height. A 1920x1080 pixel image and a 1280x720 pixel image both have a 16:9 aspect ratio.

Maintaining aspect ratio is important when resizing images or videos. If you change the width without adjusting the height proportionally the image will appear stretched or squashed. This tool calculates the missing dimension automatically so the image scales correctly.

Common Aspect Ratios

16:9 is the standard for HD video, YouTube, and most monitors. 4:3 is the older TV and monitor standard. 1:1 is used for Instagram square posts and profile pictures. 9:16 is used for vertical video on TikTok, Instagram Reels, and YouTube Shorts. 21:9 is the ultrawide monitor and cinema format.


Frequently Asked Questions

What is the Open Graph image size?

The recommended Open Graph image size for social sharing is 1200x630 pixels which is approximately a 1.91:1 aspect ratio. This is the size Facebook, LinkedIn, and Twitter use when displaying link previews. Images smaller than this may appear cropped or blurry.

Is my data stored?

No. All calculations happen in your browser. Nothing is sent to any server.