B10 paper size and dimensions
B10 measures 31 × 44 mm, which is 3.1 × 4.4 cm or 1.22 × 1.73 inches. It is the smallest size in the B series.
Contents of this page
B10, portrait
31 × 44mm
- Centimetres
- 3.1 × 4.4 cm
- Inches
- 1.22 × 1.73 in
- Pixels at 300 dpi
- 366 × 520 px
- Points (pt)
- 88 × 125 pt
- Area
- 0.0014 m²
- Weight at 80 gsm
- 0.11 g
A UK passport photo measures 35 × 45 mm, only a little larger than B10. In terms of area, B10 is exactly one 1024th of B0: halve a sheet one metre wide ten times and you end up with a card just over three centimetres across.
B10 in every unit
| Unit | Width × height |
|---|---|
| Millimetres | 31 × 44 mm |
| Centimetres | 3.1 × 4.4 cm |
| Metres | 0.031 × 0.044 m |
| Inches | 1.22 × 1.73 in |
| DTP points (1/72 in) | 88 × 125 pt |
| Area | 13.6 cm², or 0.0014 m² |
| Diagonal | 53.8 mm |
| Aspect ratio | 1 : 1.419 |
B10 in pixels
| Resolution | Pixels | Megapixels | Good for |
|---|---|---|---|
| 72 dpi | 88 × 125 px | 0.01 MP | Screen, preview |
| 96 dpi | 117 × 166 px | 0.02 MP | Screen (Windows default) |
| 150 dpi | 183 × 260 px | 0.05 MP | Large format, posters seen from a distance |
| 300 dpi | 366 × 520 px | 0.19 MP | Offset and digital print |
| 600 dpi | 732 × 1039 px | 0.76 MP | Line art, fine detail |
With 3 mm bleed the document is 37 × 50 mm, which is 437 × 591 px at 300 dpi.
The smallest sizes compared
At the smallest end, the order of the series is easy to see. D10 (24 × 34 mm) is smallest, followed by A10 (26 × 37 mm) and C10 (28 × 40 mm), with B10 (31 × 44 mm) the largest. An A10 card therefore fits in a C10 envelope, and both together in a B10 sleeve.
| Size | mm | Area | Compared with B10 |
|---|---|---|---|
| B9 | 44 × 62 mm | 27.3 cm² | twice the area |
| B10 | 31 × 44 mm | 13.6 cm² | |
| C10 | 28 × 40 mm | 11.2 cm² | 82 % of the area |
| A10 | 26 × 37 mm | 9.6 cm² | 71 % of the area |
| D10 | 24 × 34 mm | 8.2 cm² | 60 % of the area |
What B10 is used for
B10 plays almost no part in daily life. It makes sense for mini labels, game tokens, small tags on jewellery or keys, and as a reference for how small the B series gets. Passport photos cannot be trimmed to B10, it is too small on every side. If you print passport photos yourself, set them up at 35 × 45 mm.
How many B10 pieces fit on a sheet?
| Sheet | Without bleed | With 3 mm bleed and 5 mm margin |
|---|---|---|
| A4 (210 × 297 mm) | 42 | 29 |
| A3 (297 × 420 mm) | 87 | 63 |
| SRA3 (320 × 450 mm) | 100 | 70 |
Frequently asked questions
How big is B10 in cm?
B10 is 3.1 cm wide and 4.4 cm tall.
Is B10 the smallest B size?
Yes. The standard B series ends at B10.
Is B10 the size of a passport photo?
No. A UK or EU passport photo is 35 × 45 mm, slightly larger than B10 on every side.
How many B10 pieces fit on A4?
42 without bleed.
How many pixels is B10 at 300 dpi?
366 × 520 pixels, or 437 × 591 pixels with 3 mm bleed.