How many hectares is 1 are?

One are (a) equals exactly 0.01 hectares (ha). Because there are 100 ares in a hectare, dividing any value in ares by 100 gives the equivalent in hectares. For example, 250 ares equals 2.5 hectares.

What is an are and where is it used?

An are (symbol: a) is a metric unit of area equal to 100 square metres or 0.01 hectares. It is part of the International System of Units (SI) but has been largely superseded in everyday use by the hectare. The are and its derivative the hectare are still used in land measurement in some European countries and in agricultural contexts. In New Zealand and Australia, land area is commonly measured in hectares or square metres rather than ares.

How do I convert hectares back to ares?

To convert hectares to ares, multiply the number of hectares by 100. For example, 3.5 hectares equals 3.5 x 100 = 350 ares. This is the exact reverse of the ares to hectares conversion, which divides by 100.

Ares to Hectares Converter

This calculator converts ares (a) to hectares (ha) and back again, using the exact metric relationship that one hectare equals 100 ares. It matters because ares still turn up in older European land records and some overseas property listings, while New Zealand land area is almost always quoted in hectares or square metres, so you need a quick, reliable way to move between the two. Enter a value in ares and choose how many decimal places you want in the answer, or work the other way by entering hectares directly, since the two fields update independently and clear each other automatically. The calculator instantly returns the equivalent in hectares and square metres in the results bar, then breaks the figure down further into acres and square kilometres, alongside a worked example showing the exact division or multiplication by 100 used to reach the answer. A plain-language result line summarises the conversion in words, and a quick reference table further down lists common are values against their matching hectare, square metre and acre figures for fast lookup. Because both units are defined within the metric system as exact powers of ten, there is no rounding error in the underlying maths, only in how many decimal places you choose to display.

Calculate.co.nz is proud to be partnered with Premium Homes, a recognised leader in eco-friendly, sustainable, and energy-efficient homebuilding. With a dedicated team and award-winning experience, they create homes that prioritise health, comfort, and long-term performance. Their founders, Andrew and Kelly, set out to raise the standard of residential construction in New Zealand by combining practical building expertise with a clear commitment to doing things better for homeowners.

Exact conversion 1 are = 0.01 ha (SI definition, no rounding).

1. Enter Area in Ares

Ares (a)

Decimal places in result

2. Reverse: Enter Hectares

Hectares (ha)

Enter a value in hectares to convert back to ares. The two fields update independently.

Conversion Result

Ares entered

100.00

Hectares
1.00
ha

Square Metres

10,000

m²

Conversion Breakdown

Input (ares)100.00 a

Conversion factor1 a = 0.01 ha

Hectares1.00 ha

Square metres10,000 m²

Acres2.4711 acres

Square kilometres0.0100 km2

Worked Example

Formulaha = a ÷ 100

Input100.00 a

Step 1100.00 ÷ 100

Result= 1.00 ha

Result: 100 ares = 1 hectare exactly. This is the definition of a hectare: 100 ares or 10,000 square metres.

Quick Reference Table

Ares (a)	Hectares (ha)	Square Metres (m²)	Acres

What Is an Are?

The are (symbol: a) is a metric unit of area equal to 100 square metres. It was introduced alongside the metre in France during the 1790s as part of the original metric system. The are is defined in the International System of Units (SI), though it is classified as a non-SI unit accepted for use with the SI. In modern usage, the are itself is rarely used directly. However, its derivative the hectare (100 ares = 10,000 m²) remains one of the most widely used units of land area worldwide.

The Conversion Formula

The relationship between ares and hectares is exact and defined by the SI:

1 are (a) = 100 square metres (m²)
1 hectare (ha) = 100 ares = 10,000 m²
To convert ares to hectares: divide by 100 (or multiply by 0.01)
To convert hectares to ares: multiply by 100

There is no rounding involved. The conversion is exact because both units are defined within the metric system using powers of 10.

Area Unit Comparison

Unit	Symbol	Square Metres	Ares	Hectares
Square metre	m²	1	0.01	0.0001
Are	a	100	1	0.01
Hectare	ha	10,000	100	1
Square kilometre	km²	1,000,000	10,000	100
Acre	ac	4,046.86	40.4686	0.404686

Where Ares Are Still Used

While most countries now use hectares and square metres for land area, the are (or its plural, ares) still appears in some contexts:

Older European land records, particularly in France and Switzerland, where the unit originated
Some agricultural and surveying documents in Continental Europe
Historical property deeds and cadastral maps
The centiare (1/100 of an are = 1 m²) is sometimes used for small plot measurements

In New Zealand, land area is measured in square metres for smaller plots and hectares for farms and larger landholdings. Neither ares nor centiares appear in common New Zealand usage.

Practical Examples

To put ares in context:

1 are = 100 m², roughly the floor area of a large New Zealand house
10 ares = 0.1 ha = 1,000 m², about the size of a typical suburban section
100 ares = 1 ha = 10,000 m², a standard hectare (about 2.47 acres)
500 ares = 5 ha = 50,000 m², a small hobby farm block

Related Calculators

Essential Calculators hub: all converters and tools.
Acres to Hectares Converter: convert imperial acres to metric hectares.
Area Conversion Calculator: convert between all common area units.
Area Calculator: calculate the area of rectangles, circles, and other shapes.

Sources and method: International Bureau of Weights and Measures (BIPM), The International System of Units (SI), 9th edition, 2019. Conversion: 1 a = 100 m² (exact); 1 ha = 100 a (exact). Acre conversion: 1 ac = 4,046.8564224 m² (exact, per international agreement 1959).

All conversions on this page are exact within the metric system. The acres conversion uses the international acre (4,046.8564224 m²) and is accurate to 10 significant figures.