A5 vs JIS B5

Q: Which is bigger, A5 or JIS B5?

JIS B5 — 182 × 257 mm against 148 × 210 mm, which is 50.5% more area.

	A5	JIS B5
Millimetres	148 × 210	182 × 257
Inches	5.83 × 8.27	7.17 × 10.12
Centimetres	14.8 × 21	18.2 × 25.7
Aspect ratio	1:1.42	1:1.41
Area	310.8 cm²	467.7 cm²

Which is bigger

A5 and JIS B5 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.

JIS B5, by 50.5% in area. JIS B5 is 34 mm wider than A5. JIS B5 is 47 mm taller.

Printing one on the other

A A5 page fits inside JIS B5 whole — print it at 100% and you get a 17 mm border down each side and 23.5 mm top and bottom.

You want	Set the print scale to	Leaves
A5 artwork on JIS B5 paper	122.4%	0.9 × 0 mm margin
JIS B5 artwork on A5 paper	81.3%	0 × 1 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

The proportions differ: A5 is 1:1.42 and JIS B5 is 1:1.41. That difference is why a layout moved between them never quite lines up — scale it to fit one edge and the other is left with 0.9 mm of unwanted margin.

Frequently asked questions

What is the difference between A5 and JIS B5?

A5 is 148 × 210 mm and JIS B5 is 182 × 257 mm. JIS B5 is the larger of the two by 50.5% in area.

Can I print A5 on JIS B5?

Yes, at 100% — A5 is smaller on both edges, so it lands inside JIS B5 with a border all round.

Which is bigger, A5 or JIS B5?

JIS B5 — 182 × 257 mm against 148 × 210 mm, which is 50.5% more area.

Related comparisons

A5 in full · JIS B5 in full · All size comparisons · All paper sizes