Square Kilometer to Acre Converter
Area · unit-converter
Convert Square Kilometer to Acre with a fixed input and output unit, step-by-step formula line, and reference tables. All calculations use square-meter-based definitions (international feet / yard standards, acre, hectare, and regional units like pyeong/tsubo).
Calculator
From: Square Kilometer (km2)
To: Acre (ac)
About Square Kilometer
The square kilometer is a metric unit equal to one million square meters. It is standard for city sizes, large properties, and regional planning in metric countries.
About Acre
The international acre is 4,046.8564224 m² by definition. Acres are standard for rural and suburban land in the US and still appear in UK property contexts.
How to convert square kilometers to acres
1 square kilometer is equal to 247.10538146716533 acre:
1 km2 = (1000000 m² ÷ 4046.8564224 m²) ac = 247.10538146716533 ac
Each square kilometer is defined as 1000000 m² and each acre as 4046.8564224 m², so one km2 equals 1000000 ÷ 4046.8564224 ac = 247.10538146716533 ac.
Let a(km2) be the numeric value of the same area measured in Square Kilometer (km2), and a(ac) the value in Acre (ac). Then:
a(ac) = a(km2) × (1000000 / 4046.8564224)
Equivalently, divide by how many km2 fit into one ac (m² per ac divided by m² per km2):
a(ac) = a(km2) ÷ 0.0040468564224
Or: acre = square kilometer ÷ 0.0040468564224
Examples
Example #1: Convert 20 km2 to acre
20 km2 = 20 km2 × (1000000/4046.8564224) ac = 4942.10762934 ac
20 km2 = 20 km2 ÷ 0.0040468564224 = 4942.10762934 ac
Example #2: Convert 50 km2 to acre
50 km2 = 50 km2 × (1000000/4046.8564224) ac = 12355.2690734 ac
50 km2 = 50 km2 ÷ 0.0040468564224 = 12355.2690734 ac
Summary
To convert Square Kilometer to Acre, multiply the value in km2 by the ratio of square meters per km2 divided by square meters per ac. Equivalently: value_ac = value_km2 × (1000000 / 4046.8564224). Numerically, 1 km2 equals 247.10538146716533 ac.
Relationship context
You are converting between metric (SI) (Square Kilometers) and US customary / imperial (Acres). Metric area is decimal from the square meter; US/imperial units use feet, yards, miles, and acres tied to international feet (0.3048 m) and related definitions. The numeric factor used here is 2.471054e+2.
Conversion tables
| Square Kilometer (km2) | Acre (ac) |
|---|---|
| 0.1 | 24.7105381467 |
| 1 | 247.105381467 |
| 2 | 494.210762934 |
| 3 | 741.316144401 |
| 4 | 988.421525869 |
| 5 | 1,235.52690734 |
| 6 | 1,482.6322888 |
| 7 | 1,729.73767027 |
| 8 | 1,976.84305174 |
| 9 | 2,223.9484332 |
| Square Kilometer (km2) | Acre (ac) |
|---|---|
| 10 | 2,471.05381467 |
| 20 | 4,942.10762934 |
| 30 | 7,413.16144401 |
| 40 | 9,884.21525869 |
| 50 | 12,355.2690734 |
| 60 | 14,826.322888 |
| 70 | 17,297.3767027 |
| 80 | 19,768.4305174 |
| 90 | 22,239.484332 |
| 100 | 24,710.5381467 |