What calculations can be done?

Calculate aspect ratio from width and height, and compute resized dimensions by specifying one value.

Are preset aspect ratios available?

Yes. Common ratios like 16:9, 4:3, 1:1 can be selected.

Is my data sent to a server?

No. All processing happens in your browser.

How do I use this tool?

Enter either the width or height and select an aspect ratio. The tool automatically calculates the other dimension. Custom ratios can also be entered.

Are decimal values supported?

Yes, decimal values are supported for input and calculation. Pixel values may be rounded to whole numbers, but detailed calculation results are also shown.

Aspect Ratio Calculator - Calculate Image and Video Sizes

Enter width and height to calculate the aspect ratio. Common ratio presets like 16:9 and 4:3 are also available.

Presets:

Width × Height

Width

Height

Ratio

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Decimal Ratio

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CSS Property

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padding-top Hack

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Preview

Resize Calculator

Original

Width

Height

→

New Width

→

New Height

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New Height

→

New Width

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How to Use

Enter width and height to calculate aspect ratio
Select from presets (16:9/4:3 etc.)
Enter new width to auto-calculate height

FAQ

What calculations can be done?: Calculate aspect ratio from width and height, and compute resized dimensions by specifying one value.
Are preset aspect ratios available?: Yes. Common ratios like 16:9, 4:3, 1:1 can be selected.
Is my data sent to a server?: No. All processing happens in your browser.
How do I use this tool?: Enter either the width or height and select an aspect ratio. The tool automatically calculates the other dimension. Custom ratios can also be entered.
Are decimal values supported?: Yes, decimal values are supported for input and calculation. Pixel values may be rounded to whole numbers, but detailed calculation results are also shown.

Related Tools

Update History

Last Updated: 2026-02-21

2026-02-21 Initial release