Convert Acres to Hectares (ac to ha)
1 acre (ac) = 0.4046856422 hectares (ha). 1 ha = 2.471053815 ac. Example: 1 ac = 1 × 0.4046856422 = 0.4046856422 ha.
Also searched as acres to ha, acres in ha, acres into hectares, ac to ha, ac in hectares, ac into hectare, acre to hectare, ac to hectares converter and how many hectares in an acre.
1 ac = 0.4046856422 ha
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk acre to hectare converter to paste a column from Excel.
How to Convert Acre to Hectare
- 1 ac = 0.4046856422 ha
- 1 ha = 2.471053815 ac
- Example: convert 1 ac to ha: 1 ac = 1 × 0.4046856422 ha = 0.4046856422 ha
Formula
ha = ac × 0.40468564224
or ha = ac ÷ 2.471053814672
Derivation from SI units:
- 1 acre = 43 560 ft² = 4 046.856 422 4 m² (international foot; the US survey foot was retired at the end of 2022)
- 1 ha = 100 m × 100 m = 10 000 m² (a non-SI unit accepted for use with the SI)
- 1 ac = 4046.8564224 m² ÷ 10000 m² per ha = 0.40468564224 ha
Both units are defined exactly, so the factor is exact. Acre definition: acre; Hectare definition: hectare.
Worked examples
- 1 ac of land is 0.4046856422 ha.
1 ac × 0.4046856422 = 0.4046856422 ha - A 100 ac farm is 40.46856422 ha.
100 ac × 0.4046856422 = 40.46856422 ha
Acre to Hectare conversion table
| Acres (ac) | Hectares (ha) |
|---|---|
| 0.1 ac | 0.04046856422 ha |
| 0.25 ac | 0.1011714106 ha |
| 0.5 ac | 0.2023428211 ha |
| 1 ac | 0.4046856422 ha |
| 2 ac | 0.8093712845 ha |
| 2.47105 ac | 0.9999984563 ha |
| 5 ac | 2.023428211 ha |
| 10 ac | 4.046856422 ha |
| 20 ac | 8.093712845 ha |
| 40 ac | 16.18742569 ha |
| 100 ac | 40.46856422 ha |
| 160 ac | 64.74970276 ha |
| 640 ac | 258.998811 ha |
Where it's used
Land areas in acres from US, UK and Indian property records are converted to hectares for metric land registers, farm statistics and international comparisons. Multiply by about 0.4047.
Acre to other area units
| Conversion | 1 ac equals |
|---|---|
| acre to hectare | 0.4046856422 ha |
| acre to square meter | 4046.856422 m² |
| acre to square centimeter | 40468564.22 cm² |
| acre to square foot | 43560 ft² |
| acre to square inch | 6272640 in² |
| acre to square millimeter | 4046856422 mm² |
| acre to square kilometre | 0.004046856422 km² |
| acre to square yard | 4840 yd² |
Show 1 more units
| acre to square mile | 0.0015625 mi² |
|---|
Frequently asked questions
How many hectares is 1 acre?
1 acre = 0.40468564224 ha exactly (43 560 ft² with the international foot).
Is an acre bigger than a hectare?
No. A hectare is about 2.47 acres, so an acre is roughly 40 % of a hectare.
How many hectares are in 1 acre?
1 ac = 0.4046856422 ha.
How do I convert acres to hectares?
Multiply the value in ac by 0.4046856422, or divide it by 2.471053815. For example, 1 ac × 0.4046856422 = 0.4046856422 ha.
Is the ac to ha conversion exact?
Yes. Both units are defined exactly, so the ratio is exact; its decimal form does not terminate and is shown here to 10 significant figures (more with the precision selector).
Sources
- NIST Handbook 44, Appendix C: General Tables of Units of Measurement, National Institute of Standards and Technology , Appendix C, units of area.
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 8, non-SI units accepted for use with the SI.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Acres to Hectares (ac to ha). Retrieved October 25, 2026, from https://scientificconverters.com/area/acres-to-hectares/
IEEE
Scientific Converters, "Convert Acres to Hectares (ac to ha)," scientificconverters.com. Accessed: Oct. 25, 2026. [Online]. Available: https://scientificconverters.com/area/acres-to-hectares/