A1 vs JIS B1

Q: Which is bigger, A1 or JIS B1?

JIS B1 — 728 × 1030 mm against 594 × 841 mm, which is 50.1% more area.

	A1	JIS B1
Millimetres	594 × 841	728 × 1030
Inches	23.39 × 33.11	28.66 × 40.55
Centimetres	59.4 × 84.1	72.8 × 103
Aspect ratio	1:1.42	1:1.41
Area	4995.5 cm²	7498.4 cm²

Which is bigger

A1 and JIS B1 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 B1, by 50.1% in area. JIS B1 is 134 mm wider than A1. JIS B1 is 189 mm taller.

Printing one on the other

A A1 page fits inside JIS B1 whole — print it at 100% and you get a 67 mm border down each side and 94.5 mm top and bottom.

You want	Set the print scale to	Leaves
A1 artwork on JIS B1 paper	122.5%	0.5 × 0 mm margin
JIS B1 artwork on A1 paper	81.6%	0 × 0.6 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: A1 is 1:1.42 and JIS B1 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 0.5 mm of unwanted margin.

Frequently asked questions

What is the difference between A1 and JIS B1?

A1 is 594 × 841 mm and JIS B1 is 728 × 1030 mm. JIS B1 is the larger of the two by 50.1% in area.

Can I print A1 on JIS B1?

Yes, at 100% — A1 is smaller on both edges, so it lands inside JIS B1 with a border all round.

Which is bigger, A1 or JIS B1?

JIS B1 — 728 × 1030 mm against 594 × 841 mm, which is 50.1% more area.

Related comparisons

A1 in full · JIS B1 in full · All size comparisons · All paper sizes