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Circumference, Area and Volume

SI Units calculation resources banner
Credit: NIST

Become familiar with methods used to calculate two-dimensional and three-dimensional objects.

Calculate Circumference, Area and Volume

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Credit: Pixabay

Measurement calculations are important in daily life. Area calculations are needed in many activities, including planning a garden, determining how much paint to cover a surface, or purchasing new carpet. Calculating volume is important when purchasing fuel, estimating beverages for a birthday celebration, planning hydration for a long hike, or selecting an appropriate storage container. Apply these basic formulas to calculate circumference, area, and volume of simple geometric shapes commonly used in weights and measures applications.  TIP: Express all dimensions in terms of the same unit - for example, in terms of meter. A computed area will then be in terms of the square of the dimensional unit used - for example, square meter (m2) - and a computed volume will be in terms of the cube of the dimensional unit used - for example, cubic meter (m3).


  • Circumference of circle: 3.1416 × diameter
  • Area of circle: 0.7854 × diameter × diameter
  • Area of rectangle: length × width
  • Capacity of rectangular bin: length × width × depth
  • Volume of cylinder: 0.7854 × diameter × diameter × height
  • Approximate capacity of container having sloping sides: vertical height × one-half the sum of top area and bottom area

Basic Definitions

  • Perimeter: The continuous line forming the boundary of a closed geometric figure.
    Diagram of a circle with the diameter, radius, and circumference shown
    Anatomy of a circle.
    Credit: Adobe Stock
  • Circumference: The distance around the edge of a circle (or any curvy shape). A type of perimeter.
  • Diameter: Any straight line segment between two points on the circumference of a circle that passes through the center of the circle. Twice the length of the radius of a circle.
  • Area: The size of a surface. The amount of space inside the boundary of flat shape or the surface of an object. Measured in square units.
  • Volume: The measurement of amount of space occupied inside the three dimensional space. Measured in cubic units.
  • Capacity: The maximum amount that an object can contain. Measured in cubic units.

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Created February 17, 2021, Updated September 20, 2023