Hectares & square kilometres
Theory
Large areas of land are measured in hectares and square kilometres. A hectare is a \(100\,\text{m}\) square, so \(1\ \text{ha} = 10\,000\,\text{m}^2\), and \(1\,\text{km}^2 = 100\ \text{ha}\).
Large pieces of land are measured in hectares (ha) and square kilometres (\(\text{km}^2\)).
A hectare is the area of a square \(100\,\text{m}\) by \(100\,\text{m}\), so \(1\ \text{ha} = 100 \times 100 = 10\,000\,\text{m}^2\).
A square kilometre is the area of a square \(1000\,\text{m}\) by \(1000\,\text{m}\), so \(1\,\text{km}^2 = 1000 \times 1000 = 1\,000\,000\,\text{m}^2\).
Comparing the two, \(1\,\text{km}^2 = 100\ \text{ha}\).
Changing to a larger unit means dividing; to a smaller unit means multiplying.
| From | To | Step |
|---|---|---|
| \(\text{m}^2\) | ha | \(\div\,10\,000\) |
| ha | \(\text{m}^2\) | \(\times\,10\,000\) |
| \(\text{km}^2\) | ha | \(\times\,100\) |
| ha | \(\text{km}^2\) | \(\div\,100\) |
How to work with hectares
- Find the area of a square by multiplying the side by itself.
- To change square metres to hectares, divide by \(10\,000\).
- To change square kilometres to hectares, multiply by \(100\).
| \(100 \times 100\) | \(=\) | \(10\,000\,\text{m}^2\) |
That is \(1\) hectare.
| \(1\,000\,000 \div 10\,000\) | \(=\) | \(100\) |
So \(1\,\text{km}^2 = 100\) ha.
| \(60\,000 \div 10\,000\) | \(=\) | \(6\) |
The reserve is \(6\) ha.
| \(3 \times 100\) | \(=\) | \(300\) |
The farm is \(300\) ha.
Common pitfalls
Frequently asked questions
How big is a hectare?
A hectare is the area of a square \(100\,\text{m}\) by \(100\,\text{m}\), which is \(10\,000\,\text{m}^2\). It is close to the size of two football fields.
How many square metres are in a hectare?
There are \(10\,000\,\text{m}^2\) in one hectare, because \(100 \times 100 = 10\,000\).
How many hectares are in a square kilometre?
There are \(100\) hectares in \(1\,\text{km}^2\). A square kilometre is \(1\,000\,000\,\text{m}^2\), and dividing by \(10\,000\) gives \(100\).
How do you change square metres to hectares?
Divide the number of square metres by \(10\,000\). For example, \(50\,000\,\text{m}^2 \div 10\,000 = 5\) ha.
Which unit should I use for a farm?
Hectares and square kilometres suit farms and large blocks of land, while square metres suit smaller areas like a yard or a room.