Exact size comparison
B5 vs A5: the book-friendly middle size is noticeably roomier.
ISO B5 is 28 mm wider and 40 mm taller than A5, giving it about 42% more area for text, diagrams, and writing space.
The short answer
B5 sits between A4 and A5; A5 is the direct half-size companion to A4.
ISO B5 is 28 mm wider and 40 mm taller than A5, giving it about 42% more area for text, diagrams, and writing space. The difference is 28 mm in width and 40 mm in height.
Side by side
ISO B5 and A5 dimensions
| Measurement | ISO B5 | A5 | Difference |
|---|---|---|---|
| Width | 176 mm / 6.93 in | 148 mm / 5.83 in | 28 mm |
| Height | 250 mm / 9.84 in | 210 mm / 8.27 in | 40 mm |
| Area | 0.044 m² | 0.0311 m² | 129 cm² |
| 300 DPI | 2079 × 2953 px | 1748 × 2480 px | Different canvas |
| Primary context | ISO publishing | ISO markets | Workflow-dependent |
Choose ISO B5 when
- A book or workbook needs more comfortable line length
- The printer confirms ISO B5
- You want a format between A4 and A5
Choose A5 when
- The piece must impose naturally on A4
- The printer and stationery use standard A-series sizes
- A smaller notebook or handout is the goal
Check whether “B5” means ISO B5 at 176 × 250 mm or JIS B5 at 182 × 257 mm before sending a cover or interior to print.
Questions people ask
ISO B5 vs A5 FAQ
Is ISO B5 the same size as A5?
No. ISO B5 is 176 × 250 mm; A5 is 148 × 210 mm.
Which is wider, ISO B5 or A5?
ISO B5 is 28 mm wider.
Which is taller, ISO B5 or A5?
ISO B5 is 40 mm taller.
Can I print one format on the other?
Often, but not at identical proportions. Check whether “B5” means ISO B5 at 176 × 250 mm or JIS B5 at 182 × 257 mm before sending a cover or interior to print.
Use the numbers