A1 vs. A4
Comparing 2 standards across 9 specifications. 8 key differences identified.
A1 is an ISO 216 standard paper size measuring 594 × 841 mm (23.4 × 33.1 inches), with an exact surface area of 0.500 square meters (half of A0). It is the premier standard format for architectural blueprints, structural engineering drawings, municipal planning maps, and large-format flipcharts.
A4 is the international standard paper format defined by ISO 216, measuring 210 × 297 mm (8.27 × 11.69 inches). Utilized by over 140 countries representing approximately 95% of the world's population, it is the universal standard for business letters, official contracts, academic papers, magazine publishing, and desktop office printers.
Specification Comparison Table
9 Parameters| Parameter / Spec | ||
|---|---|---|
|
Width × Height (Metric)
|
594 × 841 mm | 210 × 297 mm |
|
Width × Height (Imperial)
|
23.4 × 33.1 in | 8.27 × 11.69 in |
|
Nominal Surface Area
|
0.500 m² (500,000 mm²) | 0.0625 m² (1/16 m² — 62,500 mm²) |
|
Exact Aspect Ratio
|
1 : √2 (1 : 1.4142) | 1 : √2 (1 : 1.4142) |
|
Weight of Standard 80 gsm Sheet
|
40.0 grams | 5.0 grams exactly |
|
Halving Relationship
|
Cut in half yields 2 sheets of A2 | — |
|
Primary Applications
|
Architectural blueprints, conference presentation boards, large flipcharts, theatrical event posters | — |
|
Weight of 500-Sheet Ream (80 gsm)
|
— | 2.50 kg (5.51 lbs) |
|
Postal Envelope Pairings
|
— | C4 (unfolded), C5 (folded once), C6 (folded twice), DL (folded in thirds) |