THE REFERENCE
Paper sizes, at a glance.
Compare nominal ISO A-series dimensions with US Letter and Legal. Every measurement is available together, with portrait width first.
Paper dimensions in mm, cm and inches
| Format | Millimetres | Centimetres | Inches, approximate |
|---|---|---|---|
| A0 | 841 × 1189 mm | 84.1 × 118.9 cm | 33.11 × 46.81 in |
| A1 | 594 × 841 mm | 59.4 × 84.1 cm | 23.39 × 33.11 in |
| A2 | 420 × 594 mm | 42 × 59.4 cm | 16.54 × 23.39 in |
| A3 | 297 × 420 mm | 29.7 × 42 cm | 11.69 × 16.54 in |
| A4 | 210 × 297 mm | 21 × 29.7 cm | 8.27 × 11.69 in |
| A5 | 148 × 210 mm | 14.8 × 21 cm | 5.83 × 8.27 in |
| A6 | 105 × 148 mm | 10.5 × 14.8 cm | 4.13 × 5.83 in |
| US Letter | 215.9 × 279.4 mm | 21.59 × 27.94 cm | 8.50 × 11.00 in |
| US Legal | 215.9 × 355.6 mm | 21.59 × 35.56 cm | 8.50 × 14.00 in |
All three units are shown together. Centimetres are millimetres ÷ 10; inches use exactly 25.4 mm per inch and are rounded to two decimal places. A-series sizes are nominal whole-millimetre dimensions. US Letter is exactly 8.5 × 11 inches; US Legal is exactly 8.5 × 14 inches.
ISO 216 defines the trimmed A-series scope. Adobe's A-series reference lists nominal millimetre dimensions; Adobe's US document reference gives Letter and Legal sizes.
The proportions of the A-series
Each successive A-series format is approximately half the area of the previous one. A3 folds to two A4 pages; A4 folds to two A5 pages; A5 folds to two A6 pages. The ideal aspect ratio is 1:√2, but the published whole-millimetre dimensions include rounding.
That rounding matters in a tightly fitted layout. Two nominal A5 widths occupy 296 mm along the 297 mm edge of A4. Four nominal A6 pieces form a 210 × 296 mm grid on a 210 × 297 mm A4 sheet, before any bleed, gaps or margins.
The diagram compares proportions at a reduced scale. It is not an actual-size measuring template. Use the listed nominal dimensions for arithmetic and the calibration reference to measure what a printer produces.
A4, Letter and Legal are different formats
US Letter is 215.9 × 279.4 mm. Compared with A4 at 210 × 297 mm, Letter is 5.9 mm wider and 17.6 mm shorter. Legal shares Letter's width but is 355.6 mm long. These formats do not share the A-series aspect ratio.
The A4 versus Letter comparison shows the different outlines, the percentage needed in each direction and what clips at 100%. To compare every supported pair, use the 81-conversion print scale table.
Choose the reference for your job
A paper dimension is not a bleed-ready footprint. For separate pieces, use the sheet layout planner. For folded pages, use the booklet page-order planner.