Geometry Calculator

Free geometry calculator. Find area, perimeter, volume and surface area for circles, rectangles, triangles, spheres and more. Step-by-step formulas.

Free Tool No Sign-up Instant Results

Shape Calculator

Comprehensive Guide & Practice

Master the mathematical principles, formulas, and step-by-step methods with worked examples and FAQs.

1

1. Geometry Formulas — Complete Reference

Geometry is the study of shapes, their properties, and the relationships between them. These formulas are essential for students from middle school through university.

2

2. Area Formulas

  • Rectangle: A = length × width
  • Square: A = side²
  • Triangle: A = ½ × base × height
  • Circle: A = π × radius² ≈ 3.14159 × r²
  • Parallelogram: A = base × height
  • Trapezoid: A = ½ × (base₁ + base₂) × height
3

3. Perimeter Formulas

  • Rectangle: P = 2(length + width)
  • Square: P = 4 × side
  • Triangle: P = a + b + c (sum of all three sides)
  • Circle (Circumference): C = 2πr = πd
4

4. Volume Formulas

  • Cube: V = side³
  • Rectangular Prism: V = l × w × h
  • Cylinder: V = π × r² × h
  • Sphere: V = (4/3) × π × r³
  • Cone: V = (1/3) × π × r² × h

See also: Triangle Calculator | Area & Perimeter Guide | Pythagorean Theorem | Volume & Surface Area