A4 size. What are the dimensions of DIN A4?

Without any doubt, A4 size is one of the most used paper formats both in printing and in our daily life, since it is the size of most of the sheets, notebooks, folders and other types of products that we frequently use in our daily life.

It is important to have a basic knowledge about the most popular sheet sizes and measurements, whether we have a company or we are dedicated to graphic design, as it is essential if we want to achieve the best possible result in our printing jobs.

In this article we are going to detail the characteristics of A4 size, its format expressed in different media units, the products in which it is most frequently used and answer some of the most frequently asked questions

What do A4 sheets look like?

A4 is part of a set or range of page sizes, called the ISO A or ISO 216 standard. This international standard is based on the German DIN 476 standard of 1922. In fact, A4 is often referred to as DIN A4. The Japanese have adopted the same range of paper sizes in their JIS P 0138-61 standard.

A4 measures 210 × 297 millimeters or 8.27 × 11.69 inches. In PostScript, its dimensions are rounded to 595 × 842 dots. Folded twice, an A4 sheet will fit in a C6-size envelope (114 × 162 mm).

By folding an A4 in two on its shorter side, an A5 document is created. Two A4 pages side by side on a sheet are equivalent to A3 paper size. This creates a range of paper sizes from A0 (which has a surface area of one square meter) to A10. The height/width ratio is kept constant for all sizes: 1:1.41 or the square root of 2. The dimensions are always rounded to the nearest millimeter.

Let’s describe different types of units of measurement used to express A4 size

Size A4 in centimeters

The measurements for A4 size in centimeters are 21.0 x 29.7 centimeters

In the following table you have the equivalence in micrometers, millimeters and meters, in case you find them useful.

Measures	Micrometers	Millimeters	Centimeters	Meters
Size A5	210000 x 297000 μm	210 x 297 mm	21,0 x 29,7 cm	0,21 x 0,297 m

DIN A4 size in pixels

For an image to output correctly, it must have a certain minimum resolution. The number of pixels depends on the required output quality.

• At 300 ppi (pixels per inch) the image must be 2480 x 3508 pixels. This is the resolution required for quality offset printing that will be viewed at close range (such as books, brochures, magazines, calendars,…). For photo books, this is also the optimal resolution, but a somewhat lower pixel count (250 ppi) is fine for high-quality photographs.
• At 150 ppi, the image should be 1240 x 1754 pixels. This is the minimum resolution for newspapers or posters viewed from a fairly close distance.

A digital camera with decent image quality and a resolution of 8 megapixels or more can be used to print high-quality A4-size photographs. A somewhat lower resolution is still valid.

A4 size in pixels per inch for low resolutions

This type of resolution is the most commonly used for conventional print jobs such as posters, books, brochures, catalogs, etc. For web images, resolutions of 72ppi or 96ppi are recommended.

For any printing job it is always recommended a resolution of at least 300ppi to get the best results, although you can also work with 150ppi, depending on the type of printing you want to do.

Size in pixels	72 PPI	96 PPI	150 PPI	300 PPI
A4	595 x 842 px	794 x 1123 px	1240 x 1754 px	2480 x 3508 px

Pixels per inch for DIN A4 at medium resolutions

Size in pixels	600 PPI	720 PPI	1200 PPI
A4	4960 x 7016 px	5953 x 8419 px	9921 x 14032 px

High resolutions for A4 in pixels per inch

Tamaño en píxeles por pulgada para resoluciones altas de 1440,2400 y 2880

Size in pixels	1440 PPI	2400 PPI	2880 PPI
A4	11906 x 16838 px	19843 x 28063 px	23811 x 33676 px

A4 size in Thou, inches, feet and yards

Aunque no son las unidades de medidas más comunes que nos vamos a encontrar, si realizas algún trabajo de imprenta o de diseño gráfico a nivel internacional, quizás te sea útil esta tabla donde podrás encontrar las medidas del tamaño A4 en unidades como pulgadas, yardas o pies, muy usadas especialmente en países angloparlantes.

Unidad de medida	Thou	Pulgadas	Pies	Yardas
Tamaño A4	8268 x 11693 thou	8.26 x 11.69 Pulgadas	0.689 x 0.974 pies	0.230 x 0.325 yd

A4 size in Thou, inches, feet and yards

Sometimes we can find that certain types of printing presses and machinery use different measurement systems to those we are used to, in this table you have some of these measurement systems for A4 size.

Unit of measure	Points	Spades	HPGL
Tamaño A4	595 x 842	49.6 x 70.2 Picas	8400 x 11880 hp

Frequently asked questions about A4 size

We will now answer some of the questions that many people often ask about the DIN A4 format.

On what type of products is A4 size typically used?

As we have already mentioned above, A4 is one of the most commonly used formats on a daily basis so it is very common to see it in products such as:

• Posters
• Books, notebooks, catalogs, magazines
• Folders
• Letters

Which size is larger A4 or A3?

A3 is a larger size than A4, to be more precise, one A3 sheet is equivalent to two A4 size sheets, just as one A4 sheet is equivalent to two A5 sheets.

The higher the A number the smaller the size, with the largest being DIN A0 and the smallest being DIN A10.

Why is it important to know the dimensions of DIN A4?

Whether you are a graphic designer or you are simply going to do any printing job, knowing the measurements of the format you are going to work with will allow you to get the best possible result when printing your work.

If, for example, you prepare a design in a very low resolution, not suitable for printing, the result will probably be worse than you expected.

Knowing in advance the pixel size of the main formats allows you to choose precisely the sizes you need to work with to ensure an optimal printing result.

If you want to know in detail the characteristics of the most commonly used sizes in printing and design, take a look at our section on sizes and measurements, where we describe everything you need to know about the main formats used in printing.