Use our area conversion calculators to convert between common metric and imperial area units. Choose a conversion below, enter the area value, and the calculator will display the converted result.
Each converter also includes the conversion formula, a worked example, a table of common values, and answers to frequently asked questions.
Area conversion calculators
Small metric area units
These calculators are useful for converting smaller surface areas measured in square millimeters, square centimeters, and square decimeters.
- Square millimeters to square centimeters — mm² to cm²
- Square centimeters to square millimeters — cm² to mm²
- Square centimeters to square decimeters — cm² to dm²
- Square decimeters to square centimeters — dm² to cm²
Land and property area conversions
Square meters, ares, and hectares are commonly used when describing rooms, buildings, gardens, construction sites, and plots of land.
- Square meters to ares — m² to a
- Ares to square meters — a to m²
- Square meters to hectares — m² to ha
- Hectares to square meters — ha to m²
Metric and imperial area conversions
Use these calculators to convert between square centimeters from the metric system and square inches used in the imperial and US customary systems.
How area conversion works
Area measures the size of a two-dimensional surface. It is expressed in square units such as square millimeters, square centimeters, square meters, square inches, or hectares.
Area conversion is different from ordinary length conversion because the conversion factor must be squared. For example:
- 1 centimeter equals 10 millimeters.
- Therefore, 1 square centimeter equals 10 × 10, or 100 square millimeters.
The same rule applies to other square units. Because 1 meter equals 100 centimeters, 1 square meter equals 100 × 100, or 10,000 square centimeters.
Common area conversion factors
| Area unit | Equivalent area |
|---|---|
| 1 square centimeter | 100 square millimeters |
| 1 square decimeter | 100 square centimeters |
| 1 square meter | 100 square decimeters |
| 1 are | 100 square meters |
| 1 hectare | 100 ares or 10,000 square meters |
| 1 square inch | 6.4516 square centimeters |
Choosing the appropriate area unit
The most suitable unit depends on the size and purpose of the surface being measured:
- Square millimeters (mm²) are suitable for very small surfaces and cross-sectional areas.
- Square centimeters (cm²) are useful for smaller objects, drawings, labels, screens, and paper.
- Square decimeters (dm²) can be used for medium-sized surfaces and in metric-system exercises.
- Square meters (m²) are commonly used for rooms, floors, walls, apartments, and buildings.
- Ares (a) are convenient for smaller plots of land. One are equals 100 m².
- Hectares (ha) are used for larger plots, agricultural land, forests, and estates.
- Square inches (in²) are used for smaller surfaces measured with imperial or US customary units.
How to use an area converter
- Select the required conversion from the list above.
- Enter the area value you want to convert.
- Review the calculated result in the destination unit.
The individual conversion pages also show the formula used in the calculation. This allows you to verify the result or perform the same conversion manually.
Area conversion accuracy and rounding
Area calculators use established conversion factors. Results containing many decimal places may be rounded to make them easier to read.
The appropriate number of decimal places depends on the purpose of the calculation. Everyday estimates usually require fewer decimal places, while engineering, technical, or scientific calculations may require greater precision.
Frequently asked questions
What is area?
Area is the amount of space covered by a two-dimensional surface. It is expressed in square units, such as mm², cm², m², in², or ft².
Why are area conversion factors squared?
Area is calculated using two dimensions, usually length multiplied by width. When a length conversion factor is applied to both dimensions, the factor is multiplied by itself.
For example, because 1 cm equals 10 mm:
1 cm² = 10 mm × 10 mm = 100 mm²
How many square meters are in one are?
One are equals 100 square meters:
1 a = 100 m²
How many square meters are in one hectare?
One hectare equals 10,000 square meters:
1 ha = 10,000 m²
How many square centimeters are in one square inch?
One square inch equals exactly 6.4516 square centimeters:
1 in² = 6.4516 cm²
Can I convert length directly into area?
No. Length and area describe different quantities. If you know the length and width of a rectangular surface, first multiply them to calculate its area. You can then use an area converter to change the result into another area unit.