Conversions

1 foot = 12 inches, 1 square foot = 144 square inches,

1 square kilometer = 1,000,000 square meters

1 square meter = 10,000 square centimetres = 1,000,000 square millimeters

1 square centimetre = 100 square millimeters

1 square yard = 9 square feet

1 square mile = 3,097,600 square yards = 27,878,400 square feet

1 square inch = 6.4516 square centimeters

1 square foot = 0.09290304 square metres

1 square yard = 0.83612736 square metres

1 square mile = 2.589988110336 square kilometers

1 are = 100 square metres

1 hectare = 100 ares = 10,000 square metres = 0.01 square kilometres

1 acre = 4,840 square yards = 43,560 square feet.

An acre is approximately 40% of a hectare.

List of formulae

Shape Formula Variables

Triangleb and h are the base and altitude (measured perpendicular to the base), respectively.

Square s is the length of one side of the square.Rectangle l and w are the lengths of the rectangle's sides (length and width).

Rhombus a and b are the lengths of the two diagonals of the rhombus.

Parallelogram b is the length of the base and h is the perpendicular height.

Trapezoida and b are the parallel sides and h the distance (height) between the parallels.

Circle r is the radius and d the diameter.