Paper Size comparison tool
A
A3
297 x 420 mm
A
A4
210 x 297 mm
What is the difference between A3 and A4?
The primary difference between A3 and A4 is that A3 is taller and wider (297 × 420 mm) compared to A4 (210 × 297 mm).
In terms of surface area, A3 is 100.0% larger than A4.
An A3 piece of paper measures 297 × 420 mm or 11.7 × 16.5 inches. Cutting it in half will create two A4 sheets of paper. A3 is part of the A series.
An A4 piece of paper measures 210 × 297 mm or 8.3 × 11.7 inches. Cutting it in half will create two A5 sheets of paper. A4 is part of the A series.