A3 vs. A4
Comparing 2 standards across 9 specifications. 8 key differences identified.
A3 is an ISO 216 standard paper size measuring 297 × 420 mm (11.7 × 16.5 inches), with a surface area of 0.125 square meters (one eighth of A0). It is the standard large-format paper supported by commercial office multifunction printers (MFPs), widely used for financial spreadsheets, two-page A4 magazine spreads, and engineering diagrams.
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)
|
297 × 420 mm | 210 × 297 mm |
|
Width × Height (Imperial)
|
11.7 × 16.5 in | 8.27 × 11.69 in |
|
Nominal Surface Area
|
0.125 m² (125,000 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
|
10.0 grams | 5.0 grams exactly |
|
Halving Relationship
|
Cut or folded in half yields 2 sheets / 4 pages of A4 | — |
|
Primary Applications
|
Office spreadsheets, folded A4 booklets, ledger accounting, small 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) |