Exact size comparison
B5 vs A5: which is bigger, and by how much?
Both ISO B5 and Japanese JIS B5 are bigger than A5. ISO B5 is 176 × 250 mm (6.93 × 9.84 inches); A5 is 148 × 210 mm (5.83 × 8.27 inches). ISO B5 gives you about 42% more area.
The short answer
ISO B5 is 28 mm wider and 40 mm taller than A5.
Both ISO B5 and Japanese JIS B5 are bigger than A5. ISO B5 is 176 × 250 mm (6.93 × 9.84 inches); A5 is 148 × 210 mm (5.83 × 8.27 inches). ISO B5 gives you about 42% more area. 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.
Check which B5 you mean
A5 vs ISO B5 vs Japanese JIS B5
| Format | Millimeters | Inches, rounded | Area compared with A5 |
|---|---|---|---|
| A5 | 148 × 210 mm | 5.83 × 8.27 in | Baseline |
| ISO B5 | 176 × 250 mm | 6.93 × 9.84 in | 41.6% more |
| JIS B5 | 182 × 257 mm | 7.17 × 10.12 in | 50.5% more |
A printer’s “B5” setting may use 182 × 257 mm, as in this Epson paper specification. Do not assume that a B5 preset is ISO B5. For the ISO formats, see ISO 216.
Reducing B5 artwork to A5
To fit the whole portrait page onto the full A5 sheet without cropping, the maximum scale is approximately 84% for ISO B5 or 81.3% for JIS B5. These calculations exclude non-printable margins; your printer may need a smaller scale. Shrinking also reduces text, ruling and diagrams.
A5 is more compact; B5 provides more writing room. For notebooks and replacement covers, check the finished product dimensions and binding—not only the page label.
Full B5 dimensions and pixels · Full A5 dimensions and pixels · Printable A-series chart
Updated September 3, 2026. Area and scale percentages are calculated from the millimeter dimensions above.
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.
A5 vs B5: which paper size is bigger?
B5 is bigger. ISO B5 is 176 × 250 mm, about 41.6% larger by area than A5 at 148 × 210 mm. JIS B5 is 182 × 257 mm, about 50.5% larger by area than A5.
Will an A5 cover fit a B5 notebook?
A cover sized only for A5 pages is too small for B5 pages. Check the notebook’s actual outer dimensions, binding and cover clearance; paper dimensions alone do not specify a finished notebook.
Use the numbers