Paper sizes in mm, cm and inches
The ISO A series used almost everywhere, the B and C series for posters and envelopes, and the North American sizes (Letter, Legal, Tabloid) that do not follow the same logic, each with its pixel size for a 300 dpi print.
A4 = 210 × 297 mm = 8.27 × 11.69 in · Letter = 216 × 279 mm = 8.5 × 11 in
| Size | mm | cm | inches | Pixels at 300 dpi | Note |
|---|---|---|---|---|---|
| A0 | 841 × 1189 mm | 84.1 × 118.9 cm | 33.11 × 46.81 in | 9933 × 14043 px | |
| A1 | 594 × 841 mm | 59.4 × 84.1 cm | 23.39 × 33.11 in | 7016 × 9933 px | |
| A2 | 420 × 594 mm | 42 × 59.4 cm | 16.54 × 23.39 in | 4961 × 7016 px | |
| A3 | 297 × 420 mm | 29.7 × 42 cm | 11.69 × 16.54 in | 3508 × 4961 px | |
| A4 | 210 × 297 mm | 21 × 29.7 cm | 8.27 × 11.69 in | 2480 × 3508 px | |
| A5 | 148 × 210 mm | 14.8 × 21 cm | 5.83 × 8.27 in | 1748 × 2480 px | |
| A6 | 105 × 148 mm | 10.5 × 14.8 cm | 4.13 × 5.83 in | 1240 × 1748 px | |
| A7 | 74 × 105 mm | 7.4 × 10.5 cm | 2.91 × 4.13 in | 874 × 1240 px | |
| A8 | 52 × 74 mm | 5.2 × 7.4 cm | 2.05 × 2.91 in | 614 × 874 px | |
| A9 | 37 × 52 mm | 3.7 × 5.2 cm | 1.46 × 2.05 in | 437 × 614 px | |
| A10 | 26 × 37 mm | 2.6 × 3.7 cm | 1.02 × 1.46 in | 307 × 437 px |
How the A series works
ISO 216 defines A0 as a sheet of one square metre whose sides are in the ratio 1 : √2 (about 1 : 1.414). That ratio has a unique property: cut the sheet in half across its long side and both halves keep the same ratio. So A1 is half of A0, A2 half of A1, and so on, and a document scales from A4 to A3 with no change of proportions, which is why photocopiers offer 141 % and 71 % enlargement. Dimensions are rounded down to whole millimetres at each step, hence 210 × 297 rather than 210.2 × 297.3. The B series starts from B0 at 1000 × 1414 mm and fills the gaps between A sizes; the C series (ISO 269) is sized so that a C envelope holds the A sheet of the same number.
B series
| Size | mm | cm | inches | Pixels at 300 dpi | Note |
|---|---|---|---|---|---|
| B0 | 1000 × 1414 mm | 100 × 141.4 cm | 39.37 × 55.67 in | 11811 × 16701 px | |
| B1 | 707 × 1000 mm | 70.7 × 100 cm | 27.83 × 39.37 in | 8350 × 11811 px | |
| B2 | 500 × 707 mm | 50 × 70.7 cm | 19.69 × 27.83 in | 5906 × 8350 px | |
| B3 | 353 × 500 mm | 35.3 × 50 cm | 13.9 × 19.69 in | 4169 × 5906 px | |
| B4 | 250 × 353 mm | 25 × 35.3 cm | 9.84 × 13.9 in | 2953 × 4169 px | |
| B5 | 176 × 250 mm | 17.6 × 25 cm | 6.93 × 9.84 in | 2079 × 2953 px | |
| B6 | 125 × 176 mm | 12.5 × 17.6 cm | 4.92 × 6.93 in | 1476 × 2079 px | |
| B7 | 88 × 125 mm | 8.8 × 12.5 cm | 3.46 × 4.92 in | 1039 × 1476 px | |
| B8 | 62 × 88 mm | 6.2 × 8.8 cm | 2.44 × 3.46 in | 732 × 1039 px | |
| B9 | 44 × 62 mm | 4.4 × 6.2 cm | 1.73 × 2.44 in | 520 × 732 px | |
| B10 | 31 × 44 mm | 3.1 × 4.4 cm | 1.22 × 1.73 in | 366 × 520 px |
C series and DL envelopes
| Size | mm | cm | inches | Pixels at 300 dpi | Note |
|---|---|---|---|---|---|
| C4 | 229 × 324 mm | 22.9 × 32.4 cm | 9.02 × 12.76 in | 2705 × 3827 px | envelope for a flat A4 sheet |
| C5 | 162 × 229 mm | 16.2 × 22.9 cm | 6.38 × 9.02 in | 1913 × 2705 px | envelope for A4 folded once (A5) |
| C6 | 114 × 162 mm | 11.4 × 16.2 cm | 4.49 × 6.38 in | 1346 × 1913 px | envelope for A4 folded twice (A6) |
| DL | 110 × 220 mm | 11 × 22 cm | 4.33 × 8.66 in | 1299 × 2598 px | envelope for A4 folded in thirds |
North American sizes
The US, Canada and a few other countries use Letter, Legal and Tabloid, defined in inches with no fixed ratio between them. Letter is close to A4 in area but a different shape; Tabloid is two Letters side by side, the same relationship as A3 to A4. The ANSI series (A to E) extends Letter upwards for engineering drawings.
| Size | mm | cm | inches | Pixels at 300 dpi | Note |
|---|---|---|---|---|---|
| Letter | 216 × 279 mm | 21.6 × 27.9 cm | 8.5 × 10.98 in | 2551 × 3295 px | 8.5 × 11 in, ANSI A |
| Legal | 216 × 356 mm | 21.6 × 35.6 cm | 8.5 × 14.02 in | 2551 × 4205 px | 8.5 × 14 in |
| Tabloid / Ledger | 279 × 432 mm | 27.9 × 43.2 cm | 10.98 × 17.01 in | 3295 × 5102 px | 11 × 17 in, ANSI B |
| Executive | 184 × 267 mm | 18.4 × 26.7 cm | 7.24 × 10.51 in | 2173 × 3154 px | 7.25 × 10.5 in |
| ANSI C | 432 × 559 mm | 43.2 × 55.9 cm | 17.01 × 22.01 in | 5102 × 6602 px | 17 × 22 in |
| ANSI D | 559 × 864 mm | 55.9 × 86.4 cm | 22.01 × 34.02 in | 6602 × 10205 px | 22 × 34 in |
| ANSI E | 864 × 1118 mm | 86.4 × 111.8 cm | 34.02 × 44.02 in | 10205 × 13205 px | 34 × 44 in |
Pixels and print resolution
The pixel column assumes 300 dots per inch, the usual print resolution: pixels = inches × 300. For screen work at 72 or 96 dpi the same page is far fewer pixels; the PPI calculator covers screens, and mm to inches converts any other dimension.
Frequently asked questions
A4 is 210 × 297 mm, that is 21.0 × 29.7 cm or 8.27 × 11.69 inches. At 300 dpi it is 2480 × 3508 pixels.
Letter (8.5 × 11 in, 216 × 279 mm) is 6 mm wider and 18 mm shorter than A4. Documents laid out for one print with clipped margins on the other, which is why office printers have a "fit to page" option.
The A series starts from A0, a sheet of exactly one square metre with sides in the ratio 1 to √2 (841 × 1189 mm). Folding any A sheet in half gives the next size with the same proportions, and A4 is A0 folded four times.
C4 (229 × 324 mm) for a flat sheet, C5 folded once, DL (110 × 220 mm) folded in thirds, C6 folded twice.