A4 vs B4
| A4 | B4 | |
|---|---|---|
| Millimetres | 210 × 297 | 250 × 353 |
| Inches | 8.27 × 11.69 | 9.84 × 13.9 |
| Centimetres | 21 × 29.7 | 25 × 35.3 |
| Aspect ratio | 1:1.41 | 1:1.41 |
| Area | 623.7 cm² | 882.5 cm² |
Which is bigger
A4 and B4 carry the same number and are not the same sheet. The Japanese B series is defined by area — JIS B0 is 1.5 square metres where A0 is 1 — so a JIS B sheet is half again the area of the A sheet of the same number, and about 22% longer on each edge. The number tells you where a sheet sits in its own series and nothing about which standard it belongs to.
B4, by 41.5% in area. B4 is 40 mm wider than A4. B4 is 56 mm taller.
Printing one on the other
A A4 page fits inside B4 whole — print it at 100% and you get a 20 mm border down each side and 28 mm top and bottom.
| You want | Set the print scale to | Leaves |
|---|---|---|
| A4 artwork on B4 paper | 118.9% | 0.4 × 0 mm margin |
| B4 artwork on A4 paper | 84% | 0 × 0.5 mm margin |
These are the numbers for the "custom scale" box in a print dialog. "Fit to page" computes the same thing, but knowing the figure tells you in advance whether the result will look deliberate or accidental.
Why the shapes matter
Both sheets have the same 1:1.41 proportions, so artwork scales between them without any cropping or extra margin — only the size changes.
Frequently asked questions
What is the difference between A4 and B4?
A4 is 210 × 297 mm and B4 is 250 × 353 mm. B4 is the larger of the two by 41.5% in area.
Can I print A4 on B4?
Yes, at 100% — A4 is smaller on both edges, so it lands inside B4 with a border all round.
Which is bigger, A4 or B4?
B4 — 250 × 353 mm against 210 × 297 mm, which is 41.5% more area.
Related comparisons
A4 in full · B4 in full · All size comparisons · All paper sizes