Convert Square Kilometer to Acre (km² → ac)

Converting square kilometers to acres is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in square kilometers

   Start with the number of square kilometers (km²) you want to convert.
2. 2
   Multiply by 247.10538

   The conversion factor from km² to ac is 247.10538. Multiply your value by this number.
3. 3
   Read the result in acres

   The result is your value in acres (ac).

Multiply the value in square kilometers by 247.10538. For the reverse direction, multiply by 0.004047.

• ✓1 km² = 100 hectares = 1,000,000 m².
• ✓1 km² = 0.386 square miles.
• ✓Multiply km × km in metric to get km² — but always keep consistent units.

• ✗Mixing km² and km when comparing geography — 10 km is a length, 10 km² is an area.
• ✗Confusing km² with the square mile (mi²) in international comparisons.
• ✗Reading "million km²" as "km²" on continental-scale maps — factor of 10⁶.

What is the Square Kilometer?

The square kilometer equals 1,000,000 square meters (or 100 hectares) and is the international standard for measuring large areas: cities, national parks, lakes, watersheds, and country-level statistics. Population density is conventionally given in people per km² (e.g., Singapore has roughly 8,400 people/km², Mongolia has fewer than 2). The largest US national park, Wrangell-St. Elias in Alaska, covers about 53,000 km². France is 643,801 km², and the largest country, Russia, spans 17 million km². The square kilometer relates to the square meter (1 km² = 1,000,000 m²), the hectare (1 km² = 100 ha), the square mile (1 km² ≈ 0.386 mi²), and the acre (1 km² ≈ 247.1 acres). Geographic information systems, climate science, and regional planning all rely on square kilometers as the base unit for area.

• Country and city geographic area reporting
• National-park and protected-area sizes
• Large-scale environmental studies (deforestation, etc.)

What is the Acre?

The acre equals exactly 4,046.8564224 square meters (or 43,560 square feet) and is the standard unit for American and British farmland, real estate, and recreational property. The unit's origin is medieval: an acre was the area a yoke of oxen could plow in one day, traditionally a strip 1 furlong (660 ft) by 1 chain (66 ft). Despite metric adoption in many fields, the acre persists in property records throughout the US and UK. A standard American football field (excluding end zones) is about 1.32 acres. The largest US state, Alaska, contains about 365 million acres. The acre relates to the square foot (43,560 ft² = 1 acre), the hectare (1 ha ≈ 2.471 acres), the square mile (640 acres = 1 mi²), and the square meter (1 acre ≈ 4,047 m²). US farms average around 446 acres, and the average UK farm is about 215 acres.

• US farmland and ranches
• UK rural property and estates
• Canadian rural property (legal survey system)