📐

Area Calculator

Calculate area and perimeter for 5 shapes: rectangle, square, circle, triangle, and trapezoid.

FREE 5 SHAPES INSTANT

Select Shape

Area
square units
units

📐 Formulas

▭ Rectangle
Area = l × w
Perimeter = 2(l + w)
□ Square
Area = s²
Perimeter = 4s
○ Circle
Area = πr²
Circumference = 2πr
△ Triangle
Area = ½ × b × h
⏢ Trapezoid
Area = ½ × (a + b) × h

💡 Examples

Room floor — Rectangle 5m × 4m

Area = 5 × 4 = 20 m²  |  Perimeter = 18 m

Pizza — Circle with radius 15 cm

Area = π × 15² = 706.86 cm²

Garden plot — Triangle base 10m, height 6m

Area = ½ × 10 × 6 = 30 m²

💡 Unit Tip

Make sure all inputs use the same unit (all in cm, or all in ft). The result will be in that unit squared (e.g. cm²).

Common Conversions

1 m²= 10.764 ft²
1 ft²= 929 cm²
1 acre= 4047 m²
1 hectare= 10,000 m²