Free online tool

Aspect Ratio Calculator

Lock image or screen proportions and solve a missing output dimension.

Simplified ratio-
Height for new width-
Width for new height-
Scale from original-

Method

Technical calculation method

The tool uses deterministic browser APIs and standard numeric or data-format rules. Inputs and outputs remain visible so addresses, dimensions, codes, and serialized data can be checked directly.

Network and hardware results follow the selected CIDR, band, pixel, or format values; verify production settings against the target system specification.

Questions

Aspect Ratio Calculator FAQ

What is aspect ratio?

Aspect ratio is width compared with height, commonly written width:height such as 16:9.

How do I resize without stretching?

Keep the original width-to-height ratio and calculate the missing dimension from the new width or height.

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