Rectangle Area Calculator

Find the area and perimeter of a rectangle.

Area 40

Perimeter 26

Diagonal 9.434

Formula: area = length × width ; perimeter = 2(length + width)

Step-by-step with your numbers:

1. Values used:

2. Length = 8

3. Width = 5

5. Area = Length x Width = 8 x 5 = 40

6. Perimeter = 26

7. Diagonal = 9.434

Did we solve your problem today?

Get the area, perimeter and diagonal of any rectangle.

The math behind it

Area = length × width. Perimeter = 2 × (length + width). Diagonal = √(length² + width²).

8 × 5 → area 40, perimeter 26, diagonal 9.43.

Is a square a rectangle?

Yes — a square is a rectangle with equal sides.