A4 Paper Size Guide

A4 is the most widely used paper size in the world and the standard format for documents, office printing and many marketing materials. It is part of the international ISO A-series paper system and is commonly used for flyers, brochures, letters and reports.

In this guide we explain the A4 paper dimensions, how it compares to other A-series sizes, and the most common uses for A4 in printing and design.

For an overview of all standard paper formats, see our paper size guide.

What Size Is A4 Paper?

The dimensions of A4 paper are:

210 × 297 mm

21 × 29.7 cm

8.27 × 11.7 inches

A4 is exactly half the size of A3, and double the size of A5.

The A-series system works by halving each sheet while keeping the same proportions.

For example:

A2 → A3

A3 → A4

A4 → A5

A5 → A6

You can explore neighbouring sizes in our guides to A3 paper size, A5 paper size, and A6 paper size.

A4 Paper Size in Different Units

A4 paper is typically measured in millimetres, but designers and printers also use centimetres, inches and pixels depending on the software being used.

Unit	Dimensions
Millimetres	210 × 297 mm
Centimetres	21 × 29.7 cm
Inches	8.27 × 11.7 in

Understanding these measurements helps ensure your artwork is set up correctly before printing.

A4 Paper Size in Pixels

When designing digitally, the pixel size of A4 depends on the resolution used.

At 300 DPI (print quality) - 2480 × 3508 pixels

At 150 DPI - 1240 × 1754 pixels

At 72 DPI (screen resolution) - 595 × 842 pixels

Using the correct resolution ensures images remain sharp when printed.

A4 Paper Size Compared to Other A-Series Sizes

The A-series paper sizes follow a consistent ratio that allows documents to scale perfectly between formats.

Paper Size	Dimension (mm)	Dimension (inches)	Typical Uses
A0	841 × 1189 mm	33.1 × 46.8 in	Large posters, architectural drawings
A1	594 × 841 mm	23.4 × 33.1 in	Posters, technical drawings
A2	420 × 594 mm	16.5 × 23.4 in	Posters, calendars
A3	297 × 420 mm	11.7 × 16.5 in	Posters, menus, presentations
A4	210 × 297 mm	8.27 × 11.7 in	Documents, flyers, brochures
A5	148 × 210 mm	5.8 × 8.3 in	Leaflets, booklets, invitations
A6	105 × 148 mm	4.1 × 5.8 in	Postcards, small flyers

Because each sheet is half the size of the previous one, artwork designed at A4 can easily be scaled up to A3 or down to A5.

For a complete overview of the A-series system, visit our paper size guide.

What Is A4 Paper Used For?

A4 is the most versatile paper size and is widely used for both office printing and marketing materials.

Common uses include:

Documents and reports
Flyers and leaflets
Brochures
Letters
Forms and certificates
Small posters

Because A4 is supported by almost all printers, it has become the standard size for everyday printing.

For smaller promotional materials, A5 and A6 are often used.

A4 vs US Letter Size

A common question is how A4 compares to US Letter size.

A4 - 210 × 297 mm

Letter - 216 × 279 mm

A4 is slightly taller and narrower than Letter. This difference is important when printing documents internationally.

A4 Paper Size in Printing

In commercial printing, A4 is one of the most common finished sizes for marketing materials.

Flyers, leaflets and brochures are frequently printed at A4 size because it provides enough space for text, images and branding while remaining easy to distribute.

When preparing artwork for A4 printing, designers should include bleed if the design runs to the edge of the page and leave a safe margin around important content.

You can learn more about paper thickness and materials in our what Is GSM paper guide.