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Aspect Ratio Calculator
Calculate missing image or video dimensions while preserving an exact aspect ratio.
How to use Aspect Ratio Calculator
- 1Enter a known width or height.
- 2Enter the width-to-height ratio, such as 16:9.
- 3Read the calculated missing dimension and ratio summary.
Key features & capabilities
Calculate width from height or height from width
Popular ratios including 16:9, 4:3, 1:1, 3:2, and 21:9
Custom width-to-height ratios
Practical dimensions for images, video, and responsive layouts
Frequently Asked Questions
What does 16:9 mean?It means the width is 16 units for every 9 units of height. A 1920×1080 display is a common 16:9 example.
Can I use decimal dimensions?Yes. Decimal results are supported and rounded to a practical precision.
Can it calculate social media sizes?Yes. Enter the target ratio for your design and one known dimension to calculate the other.
About this tool
Aspect Ratio Calculator is designed for practical everyday workflows. The interface is intentionally lightweight, responsive, and usable on desktop and mobile. The conversion or calculation runs in your browser, so ordinary input data is processed on the current device rather than uploaded as part of the tool operation.