Rectangle Calculator — Area, Perimeter & Diagonal

Rectangle Calculator

Calculate area, perimeter, and diagonal of a rectangle. Convert between square inches, square feet, square meters, and more.

Rectangle Dimensions

Rectangle properties

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

1 sq in = 6.4516 cm² = 0.00694 sq ft

Calculation Options

Rectangle formulas

Area = L × W
Perimeter = 2L + 2W
Diagonal = √(L² + W²)

Rectangle Calculation Results

Area & properties
Unit Comparison
Formulas

Area in Square Inches

80 in²
10 in × 8 in
Perimeter 36in | 3.00 ft
Diagonal 12.81in | 1.07 ft
Square Feet
0.56 ft²
Square Meters
0.05 m²
Square Centimeters
516.13 cm²
Square Yards
0.06 yd²

Area Unit Comparison

Unit Abbreviation Square Inches Equivalent Area Common Use

Rectangle Formulas

Area

Formula: Area = Length × Width
Example: L = 10 in, W = 8 in → Area = 80 in²

Perimeter

Formula: Perimeter = 2 × (Length + Width)
Example: L = 10 in, W = 8 in → P = 2 × 18 = 36 in

Diagonal

Formula: d = √(Length² + Width²)
Example: L = 10 in, W = 8 in → d = √(100+64) = √164 ≈ 12.81 in

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