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International Envelope Series



Belonging to the ISO 216 standard, the C7 paper size is a unique and versatile member of the 'C' series. This series is specifically designed for envelopes, with each size being suitable to contain the corresponding 'A' series paper when folded in half.

The dimensions of a C7 envelope are 81mm x 114mm or 3.2 inches x 4.5 inches if you prefer imperial measurements. This makes it an ideal choice for enclosing A7 documents or other smaller items such as tickets, coins, or stamps.

C7 paper dimensions


View All International Envelope Series

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

Interestingly, the aspect ratio of all 'C' series sizes is the square root of two (√2), just like their 'A' and 'B' counterparts. This ratio ensures that when you fold or cut a piece of C7 paper in half parallel to its shorter sides, you'll end up with two smaller pieces that have exactly the same aspect ratio as your original sheet.

In terms of its usage in different regions around the world, it's worth noting that while ANSI standards dominate in North America, ISO standards including C7 are more widely accepted globally. Therefore, understanding this particular paper size can be beneficial for international correspondence and business transactions.

Overall, despite its small stature compared to other members of its family like C4 or C5 sizes, don't underestimate the power and potential utility of a humble piece of C7 paper!

Other Formats in the International Envelope Series

Interesting facts about C7

1: C7 Paper Size

C7 paper is part of the ISO 216 standard, which defines the A, B, and C series of paper sizes. It measures 81 mm × 114 mm or approximately 3.2 inches × 4.5 inches.

2: Envelope Usage

C7 paper is commonly used for envelopes that fit A7-sized cards or invitations. Its compact size makes it ideal for small notes or correspondence.

3: International Standard

The ISO C series sizes are widely used internationally, ensuring compatibility across different countries and industries. This standardization facilitates efficient printing and document handling worldwide.

4: Proportional Ratios

The C series sizes maintain a consistent aspect ratio of √2 (approximately 1:1.414). This means that when you fold a sheet in half along its longer side, you get two smaller sheets with the same proportions.

5: Origin of ISO Paper Sizes

The ISO paper size system originated from a German standard called DIN (Deutsche Industrie Norm). It was later adopted by the International Organization for Standardization (ISO) in the mid-20th century.

6: Enlarging and Reducing Sizes

The C series sizes are designed to allow easy enlargement or reduction while maintaining their aspect ratio. For example, if you enlarge a C7 sheet by doubling its dimensions, it becomes a C6 sheet.

7: Common Uses

Besides envelopes, C7 paper can be used for various purposes such as business cards, small notepads, labels, or as inserts for compact information booklets.

8: C7 and A7 Relationship

C7 paper is exactly half the size of A6 paper. This means that two C7 sheets placed side by side will have the same dimensions as an A6 sheet.

9: Historical Paper Sizes

Prior to the standardization of paper sizes, different countries and regions had their own unique systems. The ISO paper size series helped streamline global communication and printing processes.

10: Paper Weight Considerations

C7 paper can come in various weights, typically measured in grams per square meter (gsm). The weight affects the thickness and durability of the paper, allowing for different applications based on specific needs.