What is acre?

An acre is a unit of area in imperial and US customary systems equal to 43,560 square feet. It is the standard unit for measuring agricultural land, property lots, and parks in the United States and United Kingdom.

Real-world uses

Acres are used for land parcels, farm sizes, and real estate in the US, UK, and some Commonwealth countries. Zoning laws often specify minimum lot sizes in acres. An American football field (including end zones) is about 1.32 acres.

History

The acre originated in medieval England as the amount of land a yoke of oxen could plough in one day. The word comes from Old English "æcer." It was standardized as a strip 1 furlong (660 ft) by 1 chain (66 ft), yielding 43,560 square feet.

Common mistakes

Assuming an acre is a square measure with specific dimensions—it is 43,560 sq ft but can be any shape. Also, confusing acres with hectares: 1 acre ≈ 0.405 hectares, so roughly 2.5 acres make one hectare.

What is hectare?

A hectare is a metric unit of area equal to 10,000 square metres. It is the standard unit for measuring agricultural land, forest areas, and large parcels of real estate in metric countries.

Real-world uses

Hectares are the standard unit for agricultural land measurement, forestry management, and urban planning worldwide. Wine regions report vineyard sizes in hectares, and environmental reports quantify habitat loss in hectares. One hectare is roughly the size of two American football fields.

History

The hectare was introduced during the French Revolution as part of the metric system, originally called a "hecto-are" (100 ares). Though not an official SI unit, it is accepted for use with SI and remains the predominant land area unit in global agriculture.

Common mistakes

Confusing hectares with acres—1 hectare is about 2.47 acres, not 1-to-1. Also, some people confuse "hectare" with "hectometre," but a hectare is 10,000 m² (100 m × 100 m), a unit of area, not length.

When is this conversion used?

Converting between acre and hectare is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region.

Worked examples

1 acre = 0.40468564 hectare

1 hectare = 10,000 square metre

How to convert acre to hectare

To convert acre to hectare, multiply the value by 0.40468564.

To convert hectare back to acre, multiply by 2.47105381.

Measurement standards

The square metre is the SI derived unit of area. The hectare (10,000 m²) is accepted for use with the SI by the BIPM, particularly for land measurement, though it is not an SI unit itself.

Did you know?

Vatican City, the world's smallest independent state, covers just 0.44 km² (about 109 acres) — smaller than many golf courses. By contrast, Russia spans over 17.1 million km², nearly 39 million times larger.

Quick reference: acre to hectare

acrehectare
0.10.04046856
0.50.20234282
10.40468564
20.80937128
52.02342821
104.04685642
2510.11714106
5020.23428211
10040.46856422
250101.17141056
500202.34282112
1,000404.68564224

Common values

acrehectare
A4 paper0.00001532 acre0.0000062 hectare
Parking space0.00308882 acre0.00125 hectare
Tennis court0.06446238 acre0.026087 hectare
Football field (soccer)1.76433242 acre0.714 hectare
Central Park, NYC842.6293508 acre341 hectare