Paper Sizes
International standards ISO 216 and ISO 269 specify 3 different paper sizes
A Series
This is the most common and well known series of paper sizes, the largest of which is the A0 which has an area of one square metre. The series is defined in the following diagram were A1 is half the size of A0, A2 is half the size of A1 and so on.
A0 | 841 × 1189 |
A1 | 594 × 841 |
A2 | 420 × 594 |
A3 | 297 × 420 |
A4 | 210 × 297 |
A5 | 148 × 210 |
A6 | 105 × 148 |
A7 | 74 × 105 |
A8 | 52 × 74 |
A9 | 37 × 52 |
A10 | 26 × 37 |
(note all sizes are in mm)
B Series
| This series is secondary to the A series. The sizes are geometric means between sizes in the A series. For example, the width of A1 is 594 mm, of A2, 420 mm. The width of B2 is set at = 499.47, which is rounded to 500 mm. (note all sizes are in mm) |
C Series
| The C series formats are geometric means between the B series format with the same number and the A series format with the same number, e.g. C2 is the geometric mean between B2 and A2. The C series formats are used mainly for envelopes. An A4 page will fit into a C4 envelope. If you fold the A4 page so that it is A5 in size, it will fit in a C5 envelope and so on. (note all sizes are in mm) |
applicability
Prior to the adoption of ISO 216, many different paper formats were used internationally. These formats did not fit into a coherent system and were defined in terms of non-metric units. The ISO 216 formats are organized around the ratio 1:√2; two sheets next to each other together have the same ratio, sideways. This simplifies copying two A4 sheets in reduced size on one, and copying an A4 sheet in magnified size on an A3 sheet or copying half an A4 sheet in magnified size on an A4 sheet. The principal countries not generally using the ISO paper sizes are the United States of America and Canada, which use the Letter, Legal, and Executive system. (Canada uses a P-series of sizes, which are the American paper sizes rounded to metric dimensions.)
paper folds
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| single, half, V-fold | letter, C-fold | accordion, Z-fold | double parallel fold |
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| cross fold | half accordion fold | gate fold |