📐 km² to ac — Square Kilometer to Acre Converter

Convert area units — square meters, square feet, acres, hectares, cents, grounds and more.

1 unit =
From
To
Formula 1 km² = 247.10516 ac
UnitNameValue
0.001 km²0.247105 ac
0.01 km²2.47105 ac
0.1 km²24.7105 ac
1 km²247.105 ac
5 km²1235.53 ac
10 km²2471.05 ac
50 km²12355.3 ac
100 km²24710.5 ac
1000 km²247105 ac
Last updated: March 2026

Square Kilometer to Acre Conversion Table

Common square kilometer values converted to acre — factor: 1 km² = 247.1 ac

Square Kilometer (km²)Acre (ac)Context
0.001 km²0.2471 acLarge park
0.01 km²2.471 acAirport
0.1 km²24.71 acTown center
0.5 km²123.6 acSmall suburb
1 km²247.1 acSuburb
5 km²1,236 acSmall town
10 km²2,471 acLarge town
50 km²1.236e+04 acSmall city
100 km²2.471e+04 acCity
500 km²1.236e+05 acLarge city
1,000 km²2.471e+05 acMetro area
5,000 km²1,236,000 acSmall country
1e+04 km²2,471,000 acSmall country
5e+04 km²12,360,000 acLarge country
1e+05 km²24,710,000 acLarge country

About Square Kilometer to Acre Conversion

Converting square kilometer to acre is common in real estate, agriculture, surveying, and construction. Property listings, land records, and planning documents often use different area units depending on the country or industry — making accurate conversion essential for cross-border transactions and international comparisons.

As a practical reference: 5 km² = 1236 acre and 10 km² = 2471 acre. For larger land areas, 100 km² = 2.471e+04 acre — a common benchmark for farm and estate valuations. The reverse: 1 ac = 0.004047 km².

All conversions use the internationally recognized factor of exactly 1 km² = 247.1 ac. Calculations are performed in IEEE 754 double-precision floating point, giving accuracy to at least 8 significant figures — more than sufficient for any practical application.

Quick Answer

Formula: Acre = Square Kilometer × 247.10516

Multiply any square kilometer value by 247.10516 to get acre. One square kilometer equals 247.10516 ac.

Reverse: Square Kilometer = Acre × 0.00404686

Worked Examples

One square kilometer
1 km² × 247.10516 = 247.10516 ac
1 km² = 247.105 acres.
One acre
0.00405 km² × 247.10516 = 1.0007759 ac
0.00405 km² = 1 acre.
10 km²
10 km² × 247.10516 = 2471.0516 ac
10 km² = 2,471 acres.
One square mile
2.59 km² × 247.10516 = 640.00237 ac
2.59 km² = 640 acres = 1 mi².

Mental Math Tricks

Exact factor

1 km² = 247.10516 ac. Memorize this for instant mental estimates.

Rounded shortcut

Use 247.1052 as a quick mental multiplier for square kilometers to acres.

Reverse check

To verify: multiply your result by 0.00404686 to recover the original km² value.

Who Uses This Conversion?

Cartographer

Measures and labels geographic features like lakes, forests, and countries in km².

Geographer

Analyzes land use, population density, and territory size in square kilometers.

Government Official

Reports national territory, protected area, and urban footprint in km².

Urban Planner

Assesses metropolitan area growth and infrastructure needs in km².

Environmental Analyst

Tracks deforestation, desertification, and habitat change in km².

Insurance Actuary

Calculates wildfire, flood, or storm risk exposure over geographic areas in km².

Frequently Asked Questions

About Square Kilometer and Acre

Square Kilometer (km²)

The square kilometer is equal to one million square meters, used for measuring large geographic areas such as countries, forests, lakes, and urban regions.

It became the standard measure for national territories and natural features as cartography evolved in the 19th and 20th centuries alongside the metric system.

Interesting fact: The world's smallest country, Vatican City, covers just 0.44 km². Russia, the largest, spans about 17.1 million km².

Acre (ac)

The acre is a unit of land area equal to 43,560 square feet or about 4,047 m². Its origins trace to medieval England where it represented the amount of land an ox could plough in a day.

Acres remain the standard land measurement unit in the US, UK, Canada, and India for agriculture, real estate, and property transactions.

Interesting fact: A US football field (including end zones) is about 1.32 acres, and a typical suburban house plot in the US is roughly 0.2 acres.