International Envelope Paper Sizes List
| Format | Width × Height(mm) | Width × Height (inches) |
|---|
| DL | 110 × 220 | 4.3 × 8.7 |
| B4 | 250 × 353 | 9.8 × 13.9 |
| B5 | 176 × 250 | 6.9 × 9.8 |
| B6 | 125 × 176 | 4.9 × 6.9 |
| C3 | 324 × 458 | 12.8 × 18.0 |
| C4 | 229 × 324 | 9.0 × 12.8 |
| C4M | 318 × 229 | 12.5 × 9.0 |
| C5 | 162 × 229 | 6.4 × 9.0 |
| C6/C5 | 114 × 229 | 4.5 × 9.0 |
| C6 | 114 × 162 | 4.5 × 6.4 |
| C64M | 318 × 114 | 12.5 × 4.5 |
| C7/C6 | 81 × 162 | 3.2 × 6.4 |
| C7 | 81 × 114 | 3.2 × 4.5 |
| CE4 | 229 × 310 | 9.0 × 12.2 |
| CE64 | 114 × 310 | 4.5 × 12.2 |
| E4 | 220 × 312 | 8.7 × 12.3 |
| EC45 | 220 × 229 | 8.7 × 9.0 |
| EC5 | 155 × 229 | 6.1 × 9.0 |
| E5 | 115 × 220 | 4.5 × 8.7 |
| E56 | 155 × 155 | 6.1 × 6.1 |
| E6 | 110 × 155 | 4.3 × 6.1 |
| E65 | 110 × 220 | 4.3 × 8.7 |
| R7 | 120 × 135 | 4.7 × 5.3 |
| S4 | 250 × 330 | 9.8 × 13.0 |
| S5 | 185 × 255 | 7.3 × 10.0 |
| S65 | 110 × 225 | 4.3 × 8.9 |
| X5 | 105 × 216 | 4.1 × 8.5 |
| EX5 | 155 × 216 | 6.1 × 8.5 |