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📐 Rectangle Calculator

Enter length and width to calculate perimeter, area, and diagonal

📊 Result Chart

❓ FAQ

How to calculate the perimeter of a rectangle?
Perimeter = 2 × (length + width). For example, length 5 cm and width 3 cm gives perimeter = 2 × (5 + 3) = 16 cm.

How to calculate the area of a rectangle?
Area = length × width. For example, length 5 cm and width 3 cm gives area = 5 × 3 = 15 cm².

How to calculate the diagonal of a rectangle?
Diagonal = √(length² + width²), by the Pythagorean theorem. For example, length 5 cm and width 3 cm gives diagonal = √(25 + 9) ≈ 5.83 cm.

What is the difference between a rectangle and a square?
A square is a special rectangle where all four sides are equal. A rectangle has equal opposite sides, but adjacent sides may differ. A square's diagonal = side × √2.