Area converter

Convert square metres, square feet, acres and hectares. Exact factors, and the acre and hectare kept clearly apart.

Common area conversions

Every area unit

UnitSymbol In square metres
Square millimetres mm² 0.000001
Square centimetres cm² 0.0001
Square metres 1
Ares a 100
Hectares ha 10,000
Square kilometres km² 1,000,000
Square inches in² 0.00064516
Square feet ft² 0.09290304
Square yards yd² 0.83612736
Acres ac 4,046.86
Square miles mi² 2,589,988.11

Questions

How big is an acre, really?

About 4,047 square metres, or roughly 70 by 58 metres if it were square — though it rarely is. The traditional definition was one chain by one furlong, the strip a team of oxen could plough in a day, which is why it is a long thin shape rather than a round number.

How many acres in a hectare?

A hectare is about 2.47 acres. The hectare is the tidier unit: it is exactly 10,000 square metres, or a square 100 metres on each side. Most of the world quotes land in hectares and only the English-speaking countries still lean on the acre.

Why isn't a square foot 12 square inches?

Because area scales with the square of length. A foot is 12 inches, so a square foot is 12 × 12 = 144 square inches. The same catch doubles again for volume, where a cubic foot is 1,728 cubic inches.

What area is a football pitch?

There is no single answer, which is why it is a poor unit despite being a popular one. FIFA allows pitches between roughly 4,050 and 10,800 square metres, so "the size of a football pitch" can vary by a factor of more than two.