A Series

A4

Belonging to the ISO 216 standard, A4 paper size stands as a globally recognized and widely utilized paper format. This international standard, originating from Germany in 1922, has been adopted by all countries worldwide except for the United States and Canada, which primarily use the ANSI series.

The dimensions of an A4 sheet measure 210 x 297 millimeters or approximately 8.27 x 11.69 inches. The aspect ratio of this format is √2:1, a unique characteristic that allows it to maintain its proportions when scaled up or down. This means if you fold an A4 sheet in half along its longest side, you will get two A5 sheets without altering the aspect ratio.

## A4 paper dimensions

#### Specs

Format | in | mm | cm | pt |
---|---|---|---|---|

2A0 | 46.81 x 66.22 | 1189 x 1682 | 119 x 168 | 3370 x 4768 |

A12 | 0.51 x 0.71 | 13 x 18 | 1 x 2 | 37 x 51 |

4A0 | 66.22 x 93.62 | 1682 x 2378 | 168 x 238 | 4768 x 6741 |

A11 | 0.71 x 1.02 | 18 x 26 | 2 x 3 | 51 x 74 |

A10 | 1.02 x 1.46 | 26 x 37 | 3 x 4 | 74 x 105 |

A3+ | 12.95 x 19.02 | 329 x 483 | 33 x 48 | 933 x 1369 |

A1+ | 23.98 x 35.98 | 609 x 914 | 61 x 91 | 1726 x 2591 |

A0+ | 35.98 x 50.87 | 914 x 1292 | 91 x 129 | 2591 x 3662 |

A6 | 4.13 x 5.83 | 105 x 148 | 11 x 15 | 298 x 420 |

A5 | 5.83 x 8.27 | 148 x 210 | 15 x 21 | 420 x 595 |

A4 | 8.27 x 11.69 | 210 x 297 | 21 x 30 | 595 x 842 |

A3 | 11.69 x 16.54 | 297 x 420 | 30 x 42 | 842 x 1191 |

A9 | 1.46 x 2.05 | 37 x 52 | 4 x 5 | 105 x 147 |

A2 | 16.54 x 23.39 | 420 x 594 | 42 x 59 | 1191 x 1684 |

A8 | 2.05 x 2.91 | 52 x 74 | 5 x 7 | 147 x 210 |

A1 | 23.39 x 33.11 | 594 x 841 | 59 x 84 | 1684 x 2384 |

A7 | 2.91 x 4.13 | 74 x 105 | 7 x 11 | 210 x 298 |

A0 | 33.11 x 46.81 | 841 x 1189 | 84 x 119 | 2384 x 3370 |

A4 paper size is versatile and multifunctional - it's used extensively in professional settings for documents such as letters, forms, reports and more. It's also popular in academic environments for writing papers or printing lecture notes.

Interestingly enough, the weight of an A4 sheet can vary depending on its purpose. For instance, standard office copy paper typically weighs around 80 grams per square meter (gsm), while premium quality papers used for brochures or presentations may weigh between 100-120 gsm.

The A4 paper size is not just another mundane office supply item but rather a product of thoughtful design based on mathematical principles and practical functionality.

#### Other Formats in the A Series

## Interesting facts about A4

#### 1: A4 Paper Size

A4 paper is the most commonly used paper size worldwide, measuring 210mm x 297mm or 8.27 inches x 11.69 inches.

#### 2: ISO Standard

A4 paper is part of the ISO 216 standard, which was first introduced in the early 20th century to establish a consistent paper size system globally.

#### 3: German Origins

The A series of paper sizes, including A4, was initially developed by Dr. Walter Porstmann, a German engineer and civil servant, in the early 1920s.

#### 4: Golden Ratio Proportions

The dimensions of A4 paper closely approximate the golden ratio (1:√2), a mathematical ratio that is considered aesthetically pleasing and harmonious.

#### 5: Universal Compatibility

A major advantage of A4 paper is its compatibility with various printing and copying devices worldwide due to its standardized dimensions.

#### 6: International Adoption

Around two-thirds of countries worldwide have officially adopted the ISO standard for paper sizes, including A-series papers like A3 and A5.

#### 7: Historical Influence

The adoption of standardized paper sizes played a significant role in facilitating international trade and communication during the industrial revolution.

##### Note:

Paper sizes can vary slightly between different regions due to historical preferences or local standards. However, these variations are generally minor deviations from the ISO standard sizes.