What are the exact dimensions of A4 paper?

A4 paper measures 210 mm in width and 297 mm in height, keeping the aspect ratio close to 1:1.41.

Why does A4 paper have an aspect ratio of 1 to 1.41?

The 1:1.41 ratio (square root of 2) allows A4 paper to be scaled up or down in size while maintaining the same shape, which is ideal for various document and printing needs.

How does the A4 aspect ratio affect printing and document layout?

Because its aspect ratio is consistent, A4 paper allows documents to be resized or folded without changing their proportions, making it versatile for printing and copying.

What Is the Aspect Ratio of A4 Paper? Explained

Learn the aspect ratio of A4 paper, why it’s 1:1.41, and how this ratio benefits printing and document formats.

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Sep 12, 2026

The aspect ratio for A4 paper is approximately 1:1.41. In more practical terms, this means that the length of an A4 sheet is about 1.41 times its width, making it ideal for a wide range of documents, including letters, forms, and standard printing tasks.

FAQs & Answers

What are the exact dimensions of A4 paper? A4 paper measures 210 mm in width and 297 mm in height, keeping the aspect ratio close to 1:1.41.
Why does A4 paper have an aspect ratio of 1 to 1.41? The 1:1.41 ratio (square root of 2) allows A4 paper to be scaled up or down in size while maintaining the same shape, which is ideal for various document and printing needs.
How does the A4 aspect ratio affect printing and document layout? Because its aspect ratio is consistent, A4 paper allows documents to be resized or folded without changing their proportions, making it versatile for printing and copying.

Watch More

If you found this explanation of the A4 paper aspect ratio helpful, be sure to check out our related videos on standard paper sizes like Letter, A3, and B5, as well as printing best practices for different paper formats.

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