 # Rectangle Calculator Online

Rectangle Side length Diagonals length Area Perimeter Calculator
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Welcome to use Rectangle side length diagonals length area perimeter calculator online. A calculator of the side length, diagonal length, area and perimeter of a Rectangle. Given any 2 variable of a Rectangle you can calculate the other 3 unknowns.

Units
Significant Figures

Length Side a Feet a = A / b = (P - 2b) / 2 = √(p2 - b2)

Length Side b Feet b = A / a = (P - 2a) / 2 = √(p2 - a2)

Diagonal length Feet q = √(a2 + b2)

Perimeter Feet P = 2a + 2b = 2(a + b)

Area Square Feet A = ab
Calculate
Clear

 a = Length Side a b = Length Side b q = Diagonal length P = Perimeter A = Area √ = Square root

* Units: Note that units of length are shown for convenience. They do not affect the calculations. Any other base unit can be substituted.

Rectangle Formulas
Given sides lengths a and b calculate diagonals, perimeter and area

q = √(a2 + b2)
P = 2a + 2b
A = ab

Given diagonals and side length a calculate side b, perimeter and area

b = √(q2 - a2)
P = 2a + 2b
A = ab

Given perimeter and side length a calculate side b, diagonals and area

b = (P - 2a) / 2
q = √(a2 + b2)
A = ab

Given area and side length a calculate side b, diagonals and perimeter

b = A / a
q = √(a2 + b2)
P = 2a + 2b