Aspect Ratio Calculator
Resize width or height while preserving the original aspect ratio. Enter dimensions and scale to any size without distortion.
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Frequently Asked Questions
What is an aspect ratio?
An aspect ratio describes the proportional relationship between an image's width and height. It is expressed as two numbers separated by a colon, such as 16:9 or 4:3. Maintaining the aspect ratio when resizing prevents distortion.
How is the new size calculated?
When you enter a new width, the new height is calculated as: new height = new width × (original height / original width). The same logic applies in reverse when you enter a new height.
What are common aspect ratios used for?
16:9 is the standard for HD video and most modern monitors. 4:3 is used for older TVs and some cameras. 1:1 is used for social media square posts. 21:9 is ultra-wide cinema format. 9:16 is vertical video for mobile and stories.