Method #1 – Area of a square from the length of one side
Calculator
Formula – How to calculate the area of a square from the length of one side
Area = Length of one side x Length of one side
or
Area = (Length of one side)2
Example
A square has the length of one side of 4 inches.
Area = 4 inches x 4 inches = 16 inches2
Method #2 – Area of a square from the perimeter
Calculator
Formula – How to calculate the area of a square using the perimeter
Area = (Perimeter ÷ 4)2
Example
A square has a perimeter of 40.
Area = (40 ÷ 4)2 = 102 = 100.
Method #3 – Area of a square from the length of the diagonal
Calculator
Formula – How to calculate the area of a square from the diagonal
Area = Diagonal2÷2
Example
A square has a diagonal length of 14 inches.
Area = 142 ÷ 2 = 196 ÷ 2 = 98