Acres to Hectares Real-World Size Comparison Table
These sizes come up in listings, farm records and planning papers. Several of them are standard US land survey units.
| Acres (ac) | Hectares (ha) | Real-World Size Benchmark |
|---|---|---|
| 0.25 ac | 0.1 ha | A quarter-acre suburban lot |
| 0.5 ac | 0.2 ha | A half-acre lot |
| 1 ac | 0.4 ha | One acre, about 76% of an American football field |
| 2.47 ac | 1 ha | About one hectare |
| 5 ac | 2.02 ha | A small hobby farm |
| 10 ac | 4.05 ha | A small mixed farm or large rural lot |
| 40 ac | 16.19 ha | A quarter of a quarter section in US land surveys |
| 100 ac | 40.47 ha | A common benchmark for a ranch or farm parcel |
| 160 ac | 64.75 ha | A quarter section of land |
| 640 ac | 259 ha | A full section, which is one square mile |
Acres to Hectares Conversion Formula — How to Convert ac to ha
hectares = acres ÷ 2.47105
Or multiply by 0.4047. Quick estimate: take 40% of the acres. For 100 acres that gives 40 ha (exact: 40.47).
Step-by-Step ac to ha Conversion Examples:
- •A quarter-acre residential lot:0.25 ÷ 2.47105 =0.10 ha
- •A 5-acre smallholding:5 ÷ 2.47105 =2.02 ha
- •A 160-acre farm quarter section:160 ÷ 2.47105 =64.75 ha
- •A 640-acre square mile:640 ÷ 2.47105 =259.00 ha
Why the Acres to Hectares Conversion Works & Common ac to ha Converter Mistakes to Avoid
An acre is 43,560 square feet, or 4,046.856 square meters. A hectare is 10,000 square meters, so one acre is 0.4047 of a hectare, and dividing by 2.47105 gives the same result. Both units are fixed by definition, so the factor is stable.
The Common ac to ha Converter Mistake: Multiplying acres by 2.47 when you should divide. 10 acres is 4.05 hectares, not 24.7, because the hectare is the larger unit and the hectare figure should be smaller. Another frequent error is mixing up a US survey acre and the international acre. The difference is tiny (about 2 parts per million) and does not matter for ordinary conversions, but it can show up in large surveys.
Where acres-to-hectares matters
Acres remain the standard for land in the US, parts of the UK and Ireland, while hectares are used almost everywhere else for official land records. The conversion appears in cross-border farmland and forestry deals, agricultural and environmental reports, and any form that insists on hectares.
- • Use ac For: US and Irish land listings, American ranch and farm records, UK planning documents in acres, Deeds and surveys written in acres
- • Use ha For: European and Asian land registers, Subsidy and grant forms in hectares, Scientific and environmental reports, International property comparisons
Rule of Thumb: An acre is a little under half a hectare: 1 ac ≈ 0.4 ha, 100 ac ≈ 40 ha and 2.5 ac ≈ 1 ha.
ac to ha Converter in Spreadsheets — Spreadsheet Shortcut (Excel & Google Sheets)
With acres in cell A1, =A1/2.47105 returns hectares and =A1*2.47105 goes back to acres. For comparing several listings, convert a whole column and sort by price per hectare.
Acres to Hectares Conversion — Frequently Asked Questions
How do I convert acres to hectares?
Divide the acres by 2.47105, or multiply by 0.4047. For example, 100 acres ÷ 2.47105 = 40.47 hectares.
How many hectares are in an acre?
One acre is 0.4047 hectares, or 4,046.86 square meters.
How many hectares is 5 acres?
5 acres is 2.02 hectares.
How many hectares is 100 acres?
100 acres is 40.47 hectares.
How many hectares is a square mile?
A square mile is 640 acres, which is 259 hectares.
How many acres is a hectare?
One hectare is 2.47105 acres. Use the hectares to acres converter for that direction.
How big is an acre?
An acre is 43,560 square feet, about 4,047 square meters, or roughly 76% of an American football field including end zones.
Is it acres to hectares or acres to ha?
They mean the same. "ha" is the symbol for hectare and "ac" is the symbol for acre. The conversion factor is 2.47105 either way.
ac to ha Quick-Reference Conversion Table
The land and area conversions you will use most when comparing property across countries.
| To convert | Operation | Example |
|---|---|---|
| ac → ha | ÷ 2.47105 | 100 ac → 40.47 ha |
| ha → ac | × 2.47105 | 10 ha → 24.71 ac |
| ac → ft² | × 43,560 | 1 ac → 43,560 ft² |
| ac → m² | × 4,046.86 | 1 ac → 4,046.86 m² |