How Land is Measured Around the World: Acres, Hectares, Mu, Tsubo, and Rai Explained

Every country measures land differently — and the unit reveals how land has historically been used and valued

Acres in the United States and United Kingdom. Hectares across most of continental Europe, South America, and international scientific contexts. Mu in China. Tsubo in Japan. Rai in Thailand. Jerib in Iran and Afghanistan. These aren't arbitrary choices — each unit reflects historical agricultural practices, property law traditions, and how rural communities understood productive land capacity.

The acre: agricultural origins

The acre's origin is practical: it was defined as the amount of land a yoke of oxen could plough in a single day. The standard value (4,047 square metres) is approximately the strip-ploughing pattern of a pair of oxen — a furlong (220 yards, about 201 metres) long and 22 yards (about 20 metres) wide.

Current use:

• United States: primary unit for agricultural land and large property parcels
• United Kingdom: still widely used in real estate and farmland, despite official metrication
• Canada, Australia, New Zealand: mixed; hectares preferred in official contexts, acres common in informal use

Property context:

• A standard UK suburban house plot: typically 0.02–0.10 acres
• An average UK farm: approximately 137 acres (UK Agriculture Census)
• A US football field (including end zones): 1.32 acres
• Central Park, New York: 843 acres

The hectare: the metric standard

One hectare = 10,000 square metres = 100m × 100m. Approximately 2.47 acres.

Adopted because:

• Aligns with the metric system — straightforward relationship to square metres
• International scientific and agricultural publications use hectares
• FAO (Food and Agriculture Organization) and UN report agricultural land in hectares
• EU farm subsidy payments are calculated per hectare

Agricultural context:

• An average EU farm: approximately 17 hectares
• An average Australian farm: approximately 4,331 hectares (vast inland stations)
• A standard football pitch: 0.68 hectares
• Average global yield of wheat: approximately 3.5 tonnes per hectare

Countries using hectares as primary unit: Germany, France, Spain, Italy, Netherlands, Brazil, India, Russia, China (alongside local units), and essentially all countries outside the US/UK orbit for official land measurement.

The mu: China's traditional measurement

The mu (亩, also romanised as mou) is China's traditional unit for agricultural land. Currently standardised at 1/15 hectare = 666.67 square metres.

Historical variation: before standardisation, the mu varied significantly by region — from approximately 200 to over 1,000 square metres depending on the local tradition. The current standardised value was established in the 20th century.

Context: China's agricultural land is allocated to rural households in mu. The average household farm in China is approximately 9–10 mu (~0.6 hectares). Farm policy, grain quotas, and rural economic statistics are all expressed in mu.

Other Chinese area units:

• Li (里): a unit of length; li² gives area
• Qing (顷): 100 mu = one qing (approximately 6.67 hectares)

The tsubo: Japan's property measurement

One tsubo = 3.306 square metres (approximately 2 tatami mats, or 35.6 square feet).

Japan's property market uses tsubo (坪) for interior space and land area in residential real estate. Apartment sizes and land prices are commonly quoted per tsubo.

Tokyo property context (approximate 2024 prices):

• Average central Tokyo apartment land price: ¥3–6 million per tsubo
• Central Tokyo small apartment (25 tsubo ≈ 82 m²): land value approximately ¥75–150 million

Conversion: 1 tsubo = 3.306 m² = 35.6 ft²

Other Japanese area units:

• Jo (畳): one tatami mat ≈ 1.65 m² (approximately half a tsubo)
• Pyeong (평): the Korean equivalent of tsubo, same size (3.306 m²) — both derived from the Chinese bu

The rai: Thailand's land measure

One rai = 1,600 square metres = 0.16 hectares = 0.40 acres.

Thai land is measured in rai (ไร่), ngan, and square wah:

• 1 rai = 4 ngan = 400 square wah
• 1 square wah = 4 square metres

Land ownership in Thailand for foreigners is complex — foreigners generally cannot own land outright but can own buildings. Land area in property listings is consistently in rai.

Context: a Bangkok suburban house plot might be 50–100 square wah (0.125–0.25 rai); a small farm in Chiang Mai might be 5–10 rai.

Practical conversion reference

How to use the Area Converter on sadiqbd.com

1. Enter the area in any unit
2. Convert to your target unit — from international standards to local traditional units
3. Use for property research — when comparing land prices internationally, convert to a common unit (hectares or acres) for apples-to-apples comparison
4. Agricultural planning — crop yield statistics are typically per hectare; convert local land measurements to hectares for benchmarking

Frequently Asked Questions

Why do UK estate agents still use acres instead of hectares? UK property law and custom evolved over centuries using acres. Farmers, landowners, and buyers are accustomed to thinking in acres. Despite the UK officially adopting metric in 1965, land and property measurement in practice has never fully converted. Similar to road distances still being in miles, acres in property is a cultural survival.

What is a square mile, and where is it used? 1 square mile = 640 acres = 259 hectares. Used primarily in the US for large areas — national park sizes, county areas, and urban area comparisons. "Section" in US land surveys = 1 square mile; US townships are 6 × 6 sections (36 square miles).

Is the Area Converter free? Yes — completely free, no sign-up required.

Land measurement is one of the most culturally persistent forms of non-metric units — acres outlasted metrication in the UK and US, tsubo survived Japan's modernisation, and mu predates much of Chinese recorded history. Understanding each unit in its context turns area conversion from a mathematical exercise into a window on how different cultures have related to land.

Try the Area Converter free at sadiqbd.com — convert between square metres, hectares, acres, square feet, and local land measurement units instantly.