Paper Size Converter — Free Online Tool

A/B + US sizes, dimensions + visuals.. Paper Size Converter is a free online tool from the ToolsRift Special Unit Converters collection. It runs entirely in your browser — nothing to install, no signup, and your data never leaves your device.

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How to use Paper Size Converter

Select a paper size to see its mm, cm and inch dimensions, a proportional rectangle preview, and a full comparison table.

Frequently asked questions

What are A4 dimensions?

A4 is 210 × 297 mm, which is 21.0 × 29.7 cm or about 8.27 × 11.69 inches.

How do ISO A sizes relate?

Each A size is half the previous one and keeps a √2:1 aspect ratio, so A5 is half an A4.

How is size converted to inches?

Inches equal millimetres divided by 25.4; centimetres equal millimetres divided by 10.

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