International Envelope Paper Sizes
DL
110 × 220
mm
B4
250 × 353
mm
B5
176 × 250
mm
B6
125 × 176
mm
C3
324 × 458
mm
C4
229 × 324
mm
C4M
318 × 229
mm
C5
162 × 229
mm
C6/C5
114 × 229
mm
C6
114 × 162
mm
C64M
318 × 114
mm
C7/C6
81 × 162
mm
C7
81 × 114
mm
CE4
229 × 310
mm
CE64
114 × 310
mm
E4
220 × 312
mm
EC45
220 × 229
mm
EC5
155 × 229
mm
E5
115 × 220
mm
E56
155 × 155
mm
E6
110 × 155
mm
E65
110 × 220
mm
R7
120 × 135
mm
S4
250 × 330
mm
S5
185 × 255
mm
S65
110 × 225
mm
X5
105 × 216
mm
EX5
155 × 216
mm
Further Information
The standard envelope sizes are defined by the international standard ISO 269. They are generally designed to be used with paper sizes that follow the ISO 216 standard. The most commonly used envelope sizes are from the C series. An A4 piece of paper will fit into a C4 envelope. The DL envelope has a different aspect ratio to the C series, which is why it does not appear in that series. The DL envelope is the most common envelope used in business. DL is short for ‘Dimension Lengthwise’, however it was previously known as DIN Lang in Germany where it originated in the 1920s. An A4 sheet of paper folded three times, parallel to its smaller sides, will fit into a DL envelope.
Format | Width × Height (mm) | Width × Height (in) |
---|---|---|
DL | 110 × 220 mm | 4.3 × 8.7 in |
B4 | 250 × 353 mm | 9.8 × 13.9 in |
B5 | 176 × 250 mm | 6.9 × 9.8 in |
B6 | 125 × 176 mm | 4.9 × 6.9 in |
C3 | 324 × 458 mm | 12.8 × 18 in |
C4 | 229 × 324 mm | 9 × 12.8 in |
C4M | 318 × 229 mm | 12.5 × 9 in |
C5 | 162 × 229 mm | 6.4 × 9 in |
C6/C5 | 114 × 229 mm | 4.5 × 9 in |
C6 | 114 × 162 mm | 4.5 × 6.4 in |
C64M | 318 × 114 mm | 12.5 × 4.5 in |
C7/C6 | 81 × 162 mm | 3.2 × 6.4 in |
C7 | 81 × 114 mm | 3.2 × 4.5 in |
CE4 | 229 × 310 mm | 9 × 12.2 in |
CE64 | 114 × 310 mm | 4.5 × 12.2 in |
E4 | 220 × 312 mm | 8.7 × 12.3 in |
EC45 | 220 × 229 mm | 8.7 × 9 in |
EC5 | 155 × 229 mm | 6.1 × 9 in |
E5 | 115 × 220 mm | 4.5 × 8.7 in |
E56 | 155 × 155 mm | 6.1 × 6.1 in |
E6 | 110 × 155 mm | 4.3 × 6.1 in |
E65 | 110 × 220 mm | 4.3 × 8.7 in |
R7 | 120 × 135 mm | 4.7 × 5.3 in |
S4 | 250 × 330 mm | 9.8 × 13 in |
S5 | 185 × 255 mm | 7.3 × 10 in |
S65 | 110 × 225 mm | 4.3 × 8.9 in |
X5 | 105 × 216 mm | 4.1 × 8.5 in |
EX5 | 155 × 216 mm | 6.1 × 8.5 in |