Standard paper sizes for printing (ISO)
Here's a quick guide to the most used standard
The C series is used only for envelopes. The area of C series sheets is the geometric mean of the areas of the A and B series sheets of the same number. This means that C4 is slightly larger than A4, and B4 slightly larger than C4. Practically this means that a letter written on A4 paper it fits inside a C4 envelope, and a C4 envelope fits inside a B4 envelope.
| A (mm x mm) | B (mm x mm) | C (mm x mm) | |
|---|---|---|---|
| 0 | 841 x 1189 | 1000 x 1414 | 917 x 1297 |
| 1 | 594 x 841 | 707 x 1000 | 648 x 917 |
| 2 | 420 x 594 | 500 x 707 | 458 x 648 |
| 3 | 297 x 420 | 353 x 500 | 324 x 458 |
| 4 | 210 x 297 | 250 x 353 | 229 x 324 |
| 5 | 148 x 210 | 176 x 250 | 162 x 229 |
| 6 | 105 x 148 | 125 x 176 | 114 x 162 |
| 7 | 74 x 105 | 88 x 125 | 81 x 114 |
| 8 | 52 x 74 | 62 x 88 | 57 x 81 |
| 9 | 37 x 52 | 44 x 62 | 40 x 57 |
| 10 | 26 x 37 | 31 x 44 | 28 x 40 |
The ISO standard specifies the following tolerances:
- ±1.5mm (0.06in) for dimensions up to 150mm (5.9in),
- ±2mm (0.08in) for lengths in the range 150 to 600mm (5.9 to 23.6in)
- ±3mm (0.12in) for any dimension above 600mm (23.6in).