▬ Area of Rectangle Calculator

Rectangle Measurements

Rectangle Formulas

A rectangle is a four-sided polygon with four right angles. Opposite sides are equal in length. It is one of the most common shapes in everyday life.

Area = Length × Width
Perimeter = 2 × (Length + Width)
Diagonal = √(Length² + Width²)

Rectangle Examples

8m × 5m
Area = 40 m²
12cm × 7cm
Area = 84 cm²
10ft × 10ft
Area = 100 ft² (square)

Frequently Asked Questions

What is the area of a rectangle 8m by 5m? ▼
Area = 8 × 5 = 40 m². Perimeter = 2(8+5) = 26 m.
What is the diagonal of a rectangle? ▼
Use the Pythagorean theorem: d = √(l² + w²). For a 3×4 rectangle: d = √(9+16) = √25 = 5.
What is a square vs a rectangle? ▼
A square is a special rectangle where all four sides are equal. All squares are rectangles, but not all rectangles are squares.