Hectares to Acres
Convert hectares to acres and back, with the reference points that make land area intuitive — a football pitch, a city block, a square mile.
One hectare (100 m × 100 m) is about 2.47 acres. An acre is 43,560 square feet.
| Hectares | Acres |
|---|---|
| 0.5 | 1.24 |
| 1 | 2.47 |
| 2 | 4.94 |
| 5 | 12.36 |
| 10 | 24.71 |
| 50 | 123.55 |
| 100 | 247.11 |
| 500 | 1235.53 |
A hectare is a square. An acre is a rectangle ten times longer than it is wide.
That is not a convention, it is the definition. 43,560 looks arbitrary and is not — an acre is one chain by one furlong, and the shape is the point.
| Unit | Length | Where it comes from |
|---|---|---|
| Link | 7.92 in | one hundredth of a chain |
| Chain | 66 ft | the surveyor's chain, 100 links |
| Furlong | 660 ft | 10 chains — the length of a ploughed furrow |
| Acre | 66 × 660 ft | 43,560 sq ft |
A furlong is how far a team of oxen was worked before being turned, because turning a plough team is slow and you do it as rarely as the field allows. A chain is how wide a strip they could finish in a day. The acre is a day's ploughing, and it has the proportions of a day's ploughing.
The hectare has no such story. It is 100 m by 100 m, exactly 10,000 square metres, defined in 1795 by people who wanted a unit rather than a description of work. Squared off, an acre is 208.7 ft on a side — a number that is not round in feet, metres, or anything else.
Which matters when you buy fence
Area is fixed; perimeter is not. One acre squared off takes 835 ft of fence. The same acre as the original chain-by-furlong strip takes 1452 ft — for exactly the same ground.
| Shape | Dimensions | Perimeter | Against the square |
|---|---|---|---|
| 1:1 (square) | 208.7 × 208.7 ft | 835 ft | 1.00× |
| 2:1 | 147.6 × 295.2 ft | 885 ft | 1.06× |
| 4:1 | 104.4 × 417.4 ft | 1,044 ft | 1.25× |
| 10:1 (chain by furlong) | 66.0 × 660.0 ft | 1,452 ft | 1.74× |
| 40:1 | 33.0 × 1320.0 ft | 2,706 ft | 3.24× |
| 100:1 | 20.9 × 2087.1 ft | 4,216 ft | 5.05× |
The traditional strip costs 617 ft more fence than the square — 74% more — and the effect keeps going. A 100:1 ribbon of one acre needs 5.0 times the fence. Every row above holds exactly one acre; nothing about the deed changes.
This is the practical reason to ask for dimensions rather than acreage when acreage is what you are quoted. Two one-acre lots can differ by hundreds of feet of fence, hedge, or road frontage, and the listing says the same number.
Each system is exact inside itself; only the bridge is not
| Relation | Value | |
|---|---|---|
| Square mile in acres | 640 | exactly — 5,280 squared divides by 43,560 with nothing left over |
| Square kilometre in hectares | 100 | exactly |
| Acre in square metres | 4046.8564224 | exactly, because the foot is exactly 0.3048 m |
| Hectare in acres | 2.4710538147 | the untidy one |
A square mile being exactly 640 acres is why the American township survey is built from square-mile sections, and why farm parcels come in halves and quarters of 640. Metric has the matching fact in 100 hectares to the square kilometre, and a hectare's perimeter is a flat 400 m. Both systems are internally tidy. It is only the conversion between them that runs on forever.
How to use
- Type an area in hectares or acres.
- Read the converted area instantly.
- Use the reference table to picture the size.
- For small plots, switch to square metres or square feet.
Frequently asked questions
How many acres in a hectare?
About 2.471 acres. A hectare is exactly 10,000 square metres — a square 100 m on a side — while an acre is 4,046.86 square metres, a figure that looks arbitrary because it is.
Why is an acre such an odd number?
Because it was defined by work rather than geometry: the area a yoke of oxen could plough in a day, formalised as one chain by one furlong, or 66 feet by 660 feet. The long thin shape reflected how hard it was to turn a plough team around.
How big is a hectare in practical terms?
Roughly one and a half football pitches, or about two and a half city blocks in a typical grid. A square 100 m on a side takes about a minute to walk across.
How many hectares in a square kilometre?
Exactly 100. This is one of the tidier features of metric land measurement — a square kilometre is 1,000 m on a side, so it holds ten hectares along each edge. A square mile, by contrast, is 640 acres.
Which countries use which?
Hectares are standard almost everywhere for agriculture and land registry, including the UK officially. Acres persist in the US, and informally in Britain and Ireland, particularly in farming and property listings, where a figure in acres often reads as more familiar than the metric equivalent.
What is a rood?
A quarter of an acre, one of several traditional subdivisions that turn up in old deeds along with perches and chains. They are effectively obsolete but still appear in historic title documents, where a plot might be described as so many acres, roods and perches.
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