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Books Series

A Format

A Format

Belonging to the ISO 216 standard, the A Format is a universally recognized paper size series. This series is characterized by its unique aspect ratio of √2:1, which ensures that when a sheet is cut in half parallel to its shorter sides, the resulting halves will retain the original aspect ratio.

The A Format's dimensions are determined by this aspect ratio and the rule that an A0 sheet has an area of 1 square meter. This results in an A0 sheet measuring approximately 841mm x 1189mm. Each subsequent size in the series (A1, A2, etc.) is half the size of its predecessor.

A Format paper dimensions


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2A046.81 x 66.221189 x 1682119 x 1683370 x 4768
A120.51 x 0.7113 x 181 x 237 x 51
4A066.22 x 93.621682 x 2378168 x 2384768 x 6741
A110.71 x 1.0218 x 262 x 351 x 74
A101.02 x 1.4626 x 373 x 474 x 105
A3+12.95 x 19.02329 x 48333 x 48933 x 1369
A1+23.98 x 35.98609 x 91461 x 911726 x 2591
A0+35.98 x 50.87914 x 129291 x 1292591 x 3662
A64.13 x 5.83105 x 14811 x 15298 x 420
A55.83 x 8.27148 x 21015 x 21420 x 595
A48.27 x 11.69210 x 29721 x 30595 x 842
A311.69 x 16.54297 x 42030 x 42842 x 1191
A91.46 x 2.0537 x 524 x 5105 x 147
A216.54 x 23.39420 x 59442 x 591191 x 1684
A82.05 x 2.9152 x 745 x 7147 x 210
A123.39 x 33.11594 x 84159 x 841684 x 2384
A72.91 x 4.1374 x 1057 x 11210 x 298
A033.11 x 46.81841 x 118984 x 1192384 x 3370

One fascinating fact about this format is that it was first adopted in Germany during World War II as a means to standardize paper sizes for efficiency and cost-effectiveness. Today, it's used globally with few exceptions such as Canada and United States where ANSI series are more prevalent.

The practicality of this format lies not only in its consistent aspect ratio but also in its scalability. Whether you're printing a small postcard or a large poster, there's an 'A' size suitable for your needs.

Whether you're dealing with design layouts or office documents, understanding the A Format can help streamline your processes and ensure compatibility across different platforms and regions.

Other Formats in the Books Series

Interesting facts about A Format

1. A Format paper is based on the international standard ISO 216.

The A Format paper sizes are part of the ISO 216 standard, which was first introduced in 1975. This standard defines the dimensions and proportions of paper sizes used globally.

2. The most common A Format size is A4.

A4 paper measures 210mm x 297mm (8.27in x 11.69in) and is widely used for printing documents, letters, and other everyday purposes. It is the default size for most printers and copiers around the world.

3. The A Format series follows a simple mathematical formula.

The aspect ratio of all A Format papers is √2:1, meaning that if you divide the longer side by the shorter side, you will always get approximately 1.4142 (the square root of 2).

4. Each larger A Format size can be obtained by folding its predecessor in half.

If you fold an A0 sheet in half along its longest side, you get two equal-sized sheets of A1 paper. Folding an A1 sheet in half gives you two sheets of A2 paper, and so on down to smaller sizes like A3, A4, and beyond.

5. The largest defined size in the series is called AO or DIN-A0.

An AO sheet measures approximately 841mm x 1189mm (33.11in x 46.81in). It serves as a reference point for calculating other sizes within the series and is often used for large posters or architectural drawings.

6. The smallest defined size in the series is called AAAA or DIN-AAAA.

AAAA paper measures approximately 74mm x 105mm (2.91in x 4.13in). It is rarely used and is sometimes referred to as "postage stamp" size due to its small dimensions.

7. A Format paper sizes are widely adopted in many countries.

The A Format series is used in over 150 countries worldwide, making it one of the most widely accepted paper size standards globally. This uniformity allows for easy compatibility and exchange of documents between different regions.

8. The A Format series was inspired by German engineer Walter Porstmann.

In the early 20th century, Porstmann proposed a system of paper sizes based on the aspect ratio of √2:1, which eventually led to the development of the ISO 216 standard and the A Format series we use today.

9. The A Format series has counterparts for larger formats called B and C Formats.

B Format papers have dimensions that maintain the same aspect ratio as their corresponding A Formats but with larger sizes, while C Format papers are used primarily for envelopes and have slightly different proportions than both A and B Formats.

10. The adoption of ISO 216 helped reduce waste in printing processes.

Prior to standardization, printers often had to stock multiple paper sizes specific to each country or region they served. The introduction of ISO 216 allowed for greater efficiency by reducing waste from unused or incompatible paper stocks.