Area & Volume Calculator

The Area and Volume Calculator computes measurements for a comprehensive range of 2D shapes — circle, triangle, rectangle, trapezoid, parallelogram, ellipse and sector — and 3D shapes including cube, rectangular prism, cylinder, sphere, cone, pyramid and triangular prism. Enter any required dimensions to instantly calculate area in square units or volume in cubic units. Essential for construction estimating, packaging design, interior planning, classroom geometry and engineering calculations.

For 2D shapes: circle area uses A equals pi times r squared; triangle area is 0.5 times base times height, or Heron formula for scalene triangles; rectangle area is length times width. For 3D shapes: cube volume is side cubed; cylinder volume is pi times r squared times height; sphere volume is (4/3) times pi times r cubed. The critical distinction in 3D is between surface area (total outer face area, used for material estimation) and volume (interior space, used for capacity and weight calculations).

In construction, area calculations determine material quantities for flooring, wall paint, roof tiles and garden turf. Volume calculations handle concrete, gravel fill and pool capacity. Always add 10 to 15 percent waste allowance to material estimates. For unit conversions between metric and imperial, use our Unit Converter. For room-specific area including irregular shapes, use our Room Area Calculator. Free, no registration required.