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Belonging to the ISO 216 standard, the 18mo paper size is a unique and often overlooked format. This particular size, also known as Sextodecimo or simply 18°, is part of an intriguing history of paper sizes that have evolved over centuries.

The ISO 216 standard, which includes the A, B and C series, has been adopted by many countries worldwide. However, it's important to note that the 18mo does not fall within these commonly used series. Instead, it hails from an older system of traditional book sizes based on the sheet size of handmade paper.

18mo 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

Historically speaking, an '18mo' refers to a single sheet that has been folded into eighteen leaves or thirty-six pages. The term 'Sextodecimo', its alternate name in bibliographic language, is derived from Latin and Italian roots meaning 'sixteenth'. This indicates that each leaf of an 18mo book would be approximately one-sixteenth the size of an uncut sheet.

In terms of dimensions under modern standards though exact measurements can vary depending on country-specific practices. For instance in North America under ANSI standards (American National Standards Institute), it may differ slightly compared to European measurements under ISO norms.

Despite its less frequent use today compared to A4 or Letter sizes for instance; designers and publishers who value uniqueness might find this format appealing for certain projects such as pocket books or small journals due to its compact nature.

In conclusion: while not part of mainstream ISO or ANSI series; understanding formats like 18mo provides valuable insight into historical printing practices and offers alternative options for those seeking differentiation in their print projects.

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Interesting facts about 18mo

1. The Origin of 18mo Paper

18mo paper, also known as 18mo size, is a type of paper that measures approximately 4.5 x 7 inches (11.4 x 17.8 cm). It belongs to the category of book sizes and is derived from the term "eighteenmo," which means "eighteen months" in Latin.

2. Historical Significance

The use of 18mo paper dates back to the early days of bookbinding when it was commonly used for small pocket-sized books or miniature editions. These books were often carried by travelers or used for personal diaries and journals.

3. Folding Technique

The manufacturing process for creating 18mo paper involves folding a larger sheet multiple times to achieve the desired dimensions. This technique allows for efficient production and reduces waste during the printing process.

4. Variations in Size

While the standard size for 18mo paper is approximately 4.5 x 7 inches, variations can occur depending on regional preferences or specific printing requirements.

5. Common Uses

In modern times, due to its compact size, 18mo paper is often utilized for pocket-sized notebooks, travel guides, and small-format novels that can easily fit into bags or pockets.

6. Compatibility with Printing Techniques

The smaller dimensions of 18mo paper make it suitable for various printing techniques such as letterpress, offset printing, and digital printing methods like laser or inkjet printers.

7. Paper Weight Options

Like other types of papers, you can find different weight options available in the market for 18mo paper. The weight of the paper affects its thickness and durability, allowing for customization based on specific printing needs.

8. Paper Series and Global Standards

18mo paper falls under the ISO 216 standard series, which is an international system for paper sizes. It belongs to the A series, which includes other popular sizes like A4 (letter size) and A5 (half-letter size).

9. Historical Evolution of Paper Sizes

The development of standardized paper sizes can be traced back to ancient China, where different sizes were used for various purposes such as official documents or artistic scrolls. Over time, these standards evolved and spread globally.

10. Adaptation in Digital Era

In today's digital age, while electronic devices have become prevalent for reading purposes, 18mo-sized e-books or digital publications are still designed to mimic the traditional dimensions of physical 18mo books.