CalcCafe

Acres to Hectares

Convert acre to hectare instantly — type a value and read the result, with the exact formula shown.

Reviewed by the CalcCafe editorial team · Last updated 1 July 2026 · How we test our tools

Example

1 ac = 0.4046856 ha, 5 ac = 2.023428 ha, 10 ac = 4.046856 ha.

Common conversions: acre to hectare

Quick reference for the ac → ha values you are most likely to need, computed with the exact factor the converter above uses. It includes the specific values people most often look up (2 ac, 15 ac, 25 ac, 4 ac, 100 ac). See also the reverse converter: Hectare to Acre.

Acre (ac)Hectare (ha)
1 ac0.404686 ha
2 ac0.809371 ha
3 ac1.2141 ha
4 ac1.6187 ha
5 ac2.0234 ha
10 ac4.0469 ha
15 ac6.0703 ha
20 ac8.0937 ha
25 ac10.1171 ha
30 ac12.1406 ha
40 ac16.1874 ha
50 ac20.2343 ha
60 ac24.2811 ha
70 ac28.328 ha
75 ac30.3514 ha
80 ac32.3749 ha
90 ac36.4217 ha
100 ac40.4686 ha
150 ac60.7028 ha
200 ac80.9371 ha
250 ac101.1714 ha
500 ac202.3428 ha
1,000 ac404.6856 ha

Hectare to Acre

Hectare (ha)Acre (ac)
1 ha2.4711 ac
5 ha12.3553 ac
10 ha24.7105 ac
50 ha123.5527 ac
100 ha247.1054 ac

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.
Is 400 ft by 400 ft 1 acre?
No, a 400 ft by 400 ft square is 160,000 square feet, and an acre is 43,560 square feet, so that plot is 160,000 ÷ 43,560 = 3.67 acres, or 3.67 × 0.4046856 = 1.49 hectares. One acre laid out as a square is only about 208.7 feet on each side (the square root of 43,560). A useful mental image of one acre is a rectangle 220 feet by 198 feet.

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Sources & references

These tools follow our methodology and provide educational estimates only — verify important figures with a qualified professional.