B Format Book Size
A B Format book measures 129 × 198 mm (5.08 × 7.8 in). It is the UK trade paperback trim, the standard for literary fiction and upmarket non-fiction paperbacks, one step up from the A Format rack paperback.
B Format measures 129 millimetres wide and 198 millimetres tall.
B Format Dimensions in Each Unit
B Format is 129 × 198 mm, which is 12.9 × 19.8 cm or 5.08 × 7.8 in.
| Unit | Width | Height | Width × height | Copy |
|---|---|---|---|---|
| Millimetres (mm) | 129 | 198 | 129 × 198 mm | |
| Centimetres (cm) | 12.9 | 19.8 | 12.9 × 19.8 cm | |
| Metres (m) | 0.129 | 0.198 | 0.129 × 0.198 m | |
| Inches (in) | 5.08 | 7.8 | 5.08 × 7.8 in | |
| Feet (ft) | 0.42 | 0.65 | 0.42 × 0.65 ft | |
| Points (pt) | 366 | 561 | 366 × 561 pt | |
| Picas (pc) | 30.5 | 46.8 | 30.5 × 46.8 pc | |
| Pixels at 72 DPI | 366 | 561 | 366 × 561 px | |
| Pixels at 150 DPI | 762 | 1169 | 762 × 1169 px | |
| Pixels at 300 DPI | 1524 | 2339 | 1524 × 2339 px | |
| Pixels at 600 DPI | 3047 | 4677 | 3047 × 4677 px |
Pixel counts follow from the resolution: pixels = millimetres ÷ 25.4 × DPI. More on the DPI and pixels page.
B Format Shape and Area
| Aspect ratio | 1 : 1.535 |
|---|---|
| Area | 0.0255 m² · 25,542 mm² |
| Diagonal | 236.3 mm · 9.3 in |
| Closest ISO size | UK trade paperback |
| Governing standard | Book trade convention (UK and US) |
B Format to Scale
Put B Format next to another size in the comparison tool.
Frequently Asked Questions
What size is a B Format paperback?
B Format is 129 by 198 mm, or about 5.08 by 7.8 inches.
What is the difference between A Format and B Format?
A Format is the smaller 110 by 178 mm rack paperback. B Format is 129 by 198 mm, used for literary fiction, with more words per page and a shorter book.
Is B Format a UK or US size?
It is a UK and Commonwealth trade size. The nearest US equivalent is the 5.25 by 8 in or 5.5 by 8.5 in paperback.
Book Sizes
✓ Dimensions per Publishing trade size; unit values derived by formula. Reviewed . Editorial Process →