What Size Is A1 in Inches?

A1 paper is 23.39 × 33.11 inches (594 × 841 mm). It is four times the area of A3 and is the standard size for large-format posters, flip charts, and architectural drawings.

A1 Conversion Table

UnitWidthHeight
Millimeters594841
Centimeters59.484.1
Inches23.3933.11
Pixels @ 300 DPI70169933
Pixels @ 150 DPI35084967

A1 Compared to Other Sizes

SizeInchesRelationship
A033.11 × 46.81Twice the area of A1
A123.39 × 33.11
A216.54 × 23.39Half the area of A1
24×36 (US poster)24 × 36Similar but slightly larger

Common Uses

  • Large posters and event signage
  • Flip chart paper
  • Architectural and engineering drawings
  • Academic conference posters
  • Art prints and exhibitions
  • Map printing

Resolution for A1 Printing

QualityDPIPixels NeededMegapixels
Professional3007016 × 993369.7 MP
Good (posters)1503508 × 496717.4 MP
Acceptable1002339 × 33117.7 MP

Most A1 posters are viewed from 3+ feet away, making 150 DPI sufficient for excellent perceived quality.

For the complete A series, see A Series Paper Sizes. For poster-specific sizes, see Poster Sizes.

Frequently Asked Questions

What is A1 paper size in inches?

A1 paper measures 23.39 x 33.11 inches (594 x 841 millimeters). It is four times the size of A3 paper and commonly used for posters and technical drawings.

How many pixels is A1 at 300 DPI?

A1 at 300 DPI is 7016 x 9933 pixels (approximately 69.7 megapixels). At 150 DPI, it is 3508 x 4967 pixels.

Is A1 the same as a standard poster size?

A1 (23.39 x 33.11 inches) is a widely used poster size internationally, similar to but not identical to the US 24x36 inch poster. A1 is 0.61 inches narrower and 2.89 inches shorter than 24x36.