Acres to Hectares Conversion (ac to ha)

Acres to Hectares Converter

Enter the area in acres below to convert it to hectares.

Result in Hectares:

1 ac = 0.404686 ha

How to Convert Acres to Hectares

The fastest way to convert acres to hectares is to use this simple formula:

hectares = acres × 0.404686

The area in hectares is equal to the area in acres multiplied by 0.404686. Since one hectare is equal to 0.404686 acres^[1], that's the conversion ratio used in the formula.

For example, here's how to convert 5 acres to hectares using the formula above.

hectares = (5 ac × 0.404686) = 2.023428 ha

conversion scale showing acres and equivalent hectares area values

How Many Hectares Are in an Acre?

There are 0.404686 hectares in an acre, which is why we use this value in the formula above.

1 ac = 0.404686 ha

Acres and hectares are both units used to measure area. Keep reading to learn more about each unit of measure.

What Is an Acre?

One acre is defined as the area equal to a space that is one chain (66 ft) by one furlong (660 ft), or 10 square chains.^[2] That's equal to 43,560 square feet or 1/640 of a square mile for those unfamiliar with those units of measure.

illustration showing the size of an acre is a parcel of land that is 66 feet by 660 feet.

The acre is a US customary and imperial unit of area. Acres can be abbreviated as ac; for example, 1 acre can be written as 1 ac.

You can use an acreage calculator to measure the area of a plot of land in acres by locating the boundaries on a map.

Learn more about acres.

What Is a Hectare?

One hectare is equal to 10,000 square meters,^[3] or the area of a square with 100 meter sides.

The hectare is an SI accepted unit for area for use with the metric system. In the metric system, "hecto" is the prefix for 10². Hectares can be abbreviated as ha; for example, 1 hectare can be written as 1 ha.

Learn more about hectares.

Acre to Hectare Conversion Table

Table showing various acre measurements converted to hectares.
Acres	Hectares
1 ac	0.404686 ha
2 ac	0.809371 ha
3 ac	1.2141 ha
4 ac	1.6187 ha
5 ac	2.0234 ha
6 ac	2.4281 ha
7 ac	2.8328 ha
8 ac	3.2375 ha
9 ac	3.6422 ha
10 ac	4.0469 ha
11 ac	4.4515 ha
12 ac	4.8562 ha
13 ac	5.2609 ha
14 ac	5.6656 ha
15 ac	6.0703 ha
16 ac	6.475 ha
17 ac	6.8797 ha
18 ac	7.2843 ha
19 ac	7.689 ha
20 ac	8.0937 ha
21 ac	8.4984 ha
22 ac	8.9031 ha
23 ac	9.3078 ha
24 ac	9.7125 ha
25 ac	10.12 ha
26 ac	10.52 ha
27 ac	10.93 ha
28 ac	11.33 ha
29 ac	11.74 ha
30 ac	12.14 ha
31 ac	12.55 ha
32 ac	12.95 ha
33 ac	13.35 ha
34 ac	13.76 ha
35 ac	14.16 ha
36 ac	14.57 ha
37 ac	14.97 ha
38 ac	15.38 ha
39 ac	15.78 ha
40 ac	16.19 ha

Table showing various acre measurements converted to hectares.

Acres

Hectares

1 ac

0.404686 ha

2 ac

0.809371 ha

3 ac

1.2141 ha

4 ac

1.6187 ha

5 ac

2.0234 ha

6 ac

2.4281 ha

7 ac

2.8328 ha

8 ac

3.2375 ha

9 ac

3.6422 ha

10 ac

4.0469 ha

11 ac

4.4515 ha

12 ac

4.8562 ha

13 ac

5.2609 ha

14 ac

5.6656 ha

15 ac

6.0703 ha

16 ac

6.475 ha

17 ac

6.8797 ha

18 ac

7.2843 ha

19 ac

7.689 ha

20 ac

8.0937 ha

21 ac

8.4984 ha

22 ac

8.9031 ha

23 ac

9.3078 ha

24 ac

9.7125 ha

25 ac

10.12 ha

26 ac

10.52 ha

27 ac

10.93 ha

28 ac

11.33 ha

29 ac

11.74 ha

30 ac

12.14 ha

31 ac

12.55 ha

32 ac

12.95 ha

33 ac

13.35 ha

34 ac

13.76 ha

35 ac

14.16 ha

36 ac

14.57 ha

37 ac

14.97 ha

38 ac

15.38 ha

39 ac

15.78 ha

40 ac

16.19 ha

References

National Oceanic and Atmospheric Administration, U.S. Coast Pilot 6, General Information, https://nauticalcharts.noaa.gov/publications/coast-pilot/files/cp6/CPB6_C01_WEB.pdf
National Institute of Standards and Technology, Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices, Handbook 44 - 2019 Edition, https://nvlpubs.nist.gov/nistpubs/hb/2019/NIST.HB.44-2019.pdf
Cambridge Dictionary, hectare, https://dictionary.cambridge.org/us/dictionary/english/hectare