Acres to Hectares
Convert acre to hectare instantly — type a value and read the result, with the exact formula shown.
Example
1 ac = 0.4046856 ha, 5 ac = 2.023428 ha, 10 ac = 4.046856 ha.
How it works
Hectare = Acre × 0.4046856. Every value is converted through a single square meter base unit using internationally defined conversion factors, so any from/to pair stays consistent.
Good to know
Converting acres to hectares comes up most often when land changes hands across borders or measurement systems: a US or UK property listing quotes acreage, but a mortgage application, EU farm subsidy form, or international real-estate portal expects hectares. Farmers comparing field sizes, surveyors filing paperwork, and buyers sizing up rural plots all need to move cleanly between the two.
The acre is a centuries-old imperial unit, historically the area a yoke of oxen could plough in a day, and it remains standard in the United States and, informally, the United Kingdom. The hectare is the metric unit of land area — 10,000 square meters, or a square 100 m on a side — and it is the legal standard for agriculture and land registration almost everywhere else in the world.
For a quick mental estimate, remember that an acre is roughly 0.4 of a hectare, so just take about 40% of your acre figure: 25 acres is close to 10 hectares. Going the other way, multiply hectares by about 2.5 to get acres. For accuracy, use the exact factor of 0.4046856.
The most common mistake is confusing this with a linear conversion or rounding too early on large parcels. Because the factor is roughly 0.4047, a 1,000-acre estate is 404.69 hectares — and rounding to a flat 0.4 would understate it by nearly 5 hectares, enough to matter in a sale or subsidy claim. Also keep acres and hectares distinct from "square" units; an acre is not a measure of length, so there is no single side dimension that defines it.
Frequently asked questions
How do you convert acre to hectare?
Multiply the number of acres by 0.4046856 to get hectares. For example, 1 ac = 0.4046856 ha.
What is 1 acre in hectares?
1 acre equals 0.4046856 hectares (1 ac = 0.4046856 ha).
How many acres are in 1 hectare?
There are 2.471054 acres in 1 hectare.
Is this converter free and private?
Yes. It runs entirely in your browser, so your inputs never leave your device, there is no sign-up, and it works offline once loaded.
Are the conversions exact?
Conversions use internationally defined factors and are exact where the definitions are exact (for example, 1 inch = 2.54 cm). Displayed results are rounded for readability.
People also ask
How many hectares is 5 acres?
5 acres equals about 2.0234 hectares (5 × 0.4046856 = 2.023428 ha).
How many acres are in 2 hectares?
2 hectares is about 4.942 acres, since 1 hectare equals 2.471054 acres.
Is a hectare bigger than an acre?
Yes. One hectare is about 2.47 acres, so a hectare is roughly two and a half times larger than an acre.
How do I convert 100 acres to hectares?
Multiply by 0.4046856: 100 acres equals 40.46856 hectares, or roughly 40.5 ha.
What is half an acre in hectares?
Half an acre (0.5 ac) is about 0.2023 hectares, or roughly 2,023 square meters.
How many square meters are in an acre and a hectare?
One acre is about 4,046.86 square meters, while one hectare is exactly 10,000 square meters.
Why is the acre-to-hectare factor 0.4046856 and not a round number?
Because the acre is defined from imperial units (43,560 square feet) while the hectare is metric (10,000 m²), so the two systems do not align to a clean ratio.
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