A4 vs. A5
Comparing 2 standards across 9 specifications. 8 key differences identified.
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.
A5 is an ISO 216 standard paper size measuring 148 × 210 mm (5.83 × 8.27 inches), created by cutting or folding an A4 sheet in half. It is the dominant global format for commercial spiral notebooks, daily planners, paperback novels, corporate marketing flyers, and restaurant menus.
Specification Comparison Table
9 Parameters| Parameter / Spec | ||
|---|---|---|
|
Width × Height (Metric)
|
210 × 297 mm | 148 × 210 mm |
|
Width × Height (Imperial)
|
8.27 × 11.69 in | 5.83 × 8.27 in |
|
Nominal Surface Area
|
0.0625 m² (1/16 m² — 62,500 mm²) | 0.03125 m² (1/32 m² — 31,250 mm²) |
|
Exact Aspect Ratio
|
1 : √2 (1 : 1.4142) | 1 : √2 (1 : 1.4142) |
|
Weight of Standard 80 gsm Sheet
|
5.0 grams exactly | 2.5 grams |
|
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) | — |
|
Halving Relationship
|
— | Cut in half yields 2 sheets of A6 |
|
Primary Applications
|
— | Stationery notebooks (Moleskine, Rhodia), marketing flyers, paperback booklets, event programs |