📘 B-series paper size chart
ISO B-series sizes from B0 to B10, used for posters, books and envelopes. Centimetres are shown by default; switch units below.
B-series paper – all sizes
| Category | Size (cm) | Area | Common uses |
|---|---|---|---|
| B0 | 100 × 141.4 cm | 14,140 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B1 | 70.7 × 100 cm | 7,070 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B2 | 50 × 70.7 cm | 3,535 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B3 | 35.3 × 50 cm | 1,765 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B4 | 25 × 35.3 cm | 882.5 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B5 | 17.6 × 25 cm | 440 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B6 | 12.5 × 17.6 cm | 220 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B7 | 8.8 × 12.5 cm | 110 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B8 | 6.2 × 8.8 cm | 54.56 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B9 | 4.4 × 6.2 cm | 27.28 cm² | Posters and books, Envelopes and folders, Large-format printing |
| B10 | 3.1 × 4.4 cm | 13.64 cm² | Posters and books, Envelopes and folders, Large-format printing |
About B-series paper
ISO B-series sizes from B0 to B10, used for posters, books and envelopes.
ISO A-series paper uses a 1:√2 aspect ratio: each size is half the area of the previous one, so A4 (210 × 297 mm) folds neatly down to A5 and enlarges to A3.
B-series paper is used for posters, books and envelopes; C-series envelopes are sized so an A4 sheet folds to fit a C5 envelope. Chinese K-sheet sizes (16K, 8K, 32K) remain common in books and notebooks.
B-series paper FAQ
What size is A4 paper?
A4 is 210 × 297 mm (21 × 29.7 cm, 8.27 × 11.69 in).
How many A4 sheets fit on A3?
Two: A3 is 297 × 420 mm, exactly twice the area of A4.