### Paper Sizes

## International Paper Sizes

You may hear sheet sizes referred to as ‘B1’ or ‘A2’, and wonder where those terms came from and what they mean. We’ll break it down here to satisfy your curiosity.

Paper size are defined by the International Standards Organization [ISO]. The ISO for paper standards is referred to as ISO 216, and is based on the German Deutsches Institut für Normung 476 standard for paper sizes.

ISO paper sizes are all based on a single aspect ratio of the square root of 2, or approximately 1:1.4142. The advantages of using an aspect ratio of √2 were first noted in 1786 by the German scientist and philosopher Georg Christoph Lichtenberg. The formats for A2, A3, B3, B4 and B5 were developed in France on proposition of the mathematician Lazare Carnot, and published for judiciary purposes in 1798 during the French Revolution. Early in the 20th century, Dr Walter Porstmann turned Lichtenberg’s idea into a proper system of different paper sizes. Porstmann’s system was introduced as a DIN standard (DIN 476) in Germany in 1922, replacing a variety of other paper formats.

**‘A’ Series Paper Sizes Formal Definition**

ISO 216:2007 defines ‘A’ paper sizes:

- ‘A’ series is the most common paper size range used in English-speaking countries.
- A2 is the most common size, measuring 210mm x 297mm (8.27 inches x 11.7 inches).
- The length divided by the width is 1.4142
- The A0 size has an area of 1 square meter:
- Each subsequent size A(n) is defined as A(n-1) cut in half parallel to its shorter sides.
- The standard length and width of each size is rounded to the nearest millimeter.

Download a Free Hi-Resolution PDF A-Series.

**‘B’ Series Paper Sizes Formal Definition**

‘B’ series paper size, while not as common as the ‘A’ series, is also defined by ISO 216:2007:

- ‘B’ series specifies the trimmed sizes of writing paper and certain classes of printed material.
- ‘B’ series also specifies the indication of the machine direction for trimmed sheets.
- The ‘B’ series uses an aspect ratio of 1:√2.
- The width and height of a ‘B’ series sheet is the geometric mean of the corresponding ‘A’ series:
- B1 is between A0 and A1 in size.

- ‘B’ series is less common in ‘office’ use; it is more regularly used in commercial printing to describe the width of a press where multiple pages are laid on one larger sheet:
- B3 paper is used to print two US letter or A4 pages side by side.
- Four pages would be printed on a B2 sheet.
- Eight pages would be printed on a B1 sheet.

Download a Free Hi-Resolution PDF B-Series.

**‘C’ Series Paper Sizes Formal Definition**

‘C’ series paper, most commonly used for envelopes, was formerly defined by ISO 269:1985, which has since been withdrawn. The information on ‘C’ series paper can now be found on papersizes.org

- The area of ‘C’ series paper is the geometric mean of the areas of the ‘A’ and B’ series paper of the same number.
- Example: C4 has a bigger area than A4, but smaller area than B4. Therefore an A4 piece of paper will fit into a C4 envelope.

- The aspect ratio of C series envelopes is 1:√2;
- An A4 sheet of paper folded in half parallel to its smaller sides will fit into a C5 envelope.
- Folded twice, the same sheet will fit into a C6 envelope.

Download a Free Hi-Resolution PDF of C-Series

Additonal Resources:

- International Standards Organization (ISO)
- Paper Sizes io
- Wikipedia
- Free Hi-Resolution PDFs of A-Series, B-Series, and C-Series

## FORMAT |
## Width × Height (mm) |
## Width × Height (in) |
---|---|---|

A0 | 841 × 1189 mm | 33.1 × 46.8 in |

A1 | 594 × 841 mm | 23.4 × 33.1 in |

A2 | 420 × 594 mm | 16.5 × 23.4 in |

A3 | 297 × 420 mm | 11.7 × 16.5 in |

A4 | 210 × 297 mm | 8.3 × 11.7 in |

A5 | 148 × 210 mm | 5.8 × 8.3 in |

A6 | 105 × 148 mm | 4.1 × 5.8 in |

A7 | 74 × 105 mm | 2.9 × 4.1 in |

A8 | 52 × 74 mm | 2 × 2.9 in |

A9 | 37 × 52 mm | 1.5 × 2 in |

A10 | 26 × 37 mm | 1 × 1.5 in |

A11 | 18 × 26 mm | 0.7 × 1 in |

A12 | 13 × 18 mm | 0.5 × 0.7 in |

A13 | 9 × 13 mm | 0.4 × 0.5 in |

2A0 | 1189 × 1682 mm | 46.8 × 66.2 in |

4A0 | 1682 × 2378 mm | 66.2 × 93.6 in |

A0+ | 914 × 1292 mm | 36 × 50.9 in |

A1+ | 609 × 914 mm | 24 × 36 in |

A3+ | 329 × 483 mm | 13 × 19 in |

## FORMAT |
## Width × Height (mm) |
## Width × Height (in) |
---|---|---|

B0 | 1000 × 1414 mm | 39.4 × 55.7 in |

B1 | 707 × 1000 mm | 27.8 × 39.4 in |

B2 | 500 × 707 mm | 19.7 × 27.8 in |

B3 | 353 × 500 mm | 13.9 × 19.7 in |

B4 | 250 × 353 mm | 9.8 × 13.9 in |

B5 | 176 × 250 mm | 6.9 × 9.8 in |

B6 | 125 × 176 mm | 4.9 × 6.9 in |

B7 | 88 × 125 mm | 3.5 × 4.9 in |

B8 | 62 × 88 mm | 2.4 × 3.5 in |

B9 | 44 × 62 mm | 1.7 × 2.4 in |

B10 | 31 × 44 mm | 1.2 × 1.7 in |

B11 | 22 × 31 mm | 0.9 × 1.2 in |

B12 | 15 × 22 mm | 0.6 × 0.9 in |

B13 | 11 × 15 mm | 0.4 × 0.6 in |

B0+ | 1118 × 1580 mm | 44 × 62.2 in |

B1+ | 720 × 1020 mm | 28.3 × 40.2 in |

B2+ | 520 × 720 mm | 20.5 × 28.3 in |

## FORMAT |
## Width × Height (mm) |
## Width × Height (in) |
---|---|---|

C0 | 917 × 1297 mm | 36.1 × 51.1 in |

C1 | 648 × 917 mm | 25.5 × 36.1 in |

C2 | 458 × 648 mm | 18 × 25.5 in |

C3 | 324 × 458 mm | 12.8 × 18 in |

C4 | 229 × 324 mm | 229 × 324 mm |

C5 | 162 × 229 mm | 6.4 × 9 in |

C6 | 114 × 162 mm | 4.5 × 6.4 in |

C7 | 81 × 114 mm | 3.2 × 4.5 in |

C8 | 57 × 81 mm | 2.2 × 3.2 in |

C9 | 40 × 57 mm | 1.6 × 2.2 in |

C10 | 28 × 40 mm | 1.1 × 1.6 in |