Calculate area, perimeter, volume, and surface area of shapes
Calculate area, perimeter, volume, and surface area for common 2D and 3D shapes. Select a shape - from circles and regular polygons to spheres, cones, and prisms - choose a unit, enter the dimensions, and get every relevant measurement at once.
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You have a right triangle with legs 3 and 4 and need the hypotenuse and area for a layout.
Triangle
right triangle, legs a = 3, b = 4
Results
hypotenuse c = 5 area = 6 perimeter = 12
By the Pythagorean theorem c = √(3²+4²) = 5, and the area of a right triangle is ½·base·height = 6. The tool computes properties for many shapes and shows the formula used, so the result is verifiable, not a black box.
Calculate area, perimeter, volume, and surface area for common 2D and 3D shapes. Select a shape - from circles and regular polygons to spheres, cones, and prisms - choose a unit, enter the dimensions, and get every relevant measurement at once.
Two-dimensional shapes (circle, ellipse, rectangle, right triangle, trapezoid, parallelogram, and regular pentagon and hexagon) return area and perimeter; the ellipse perimeter uses Ramanujan's approximation. Three-dimensional shapes (sphere, cylinder, cone, cube, square pyramid, and triangular prism) return volume and surface area, and the cube also reports its space diagonal. The right-triangle mode takes a base and height and derives the hypotenuse for the perimeter. A unit selector (mm, cm, m, km, in, ft, yd) labels the results, with area in squared units and volume in cubed units.
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You pick a unit (mm, cm, m, km, in, ft, yd) and the results are labeled accordingly - lengths in that unit, areas in squared units, and volumes in cubed units. The math is the same regardless of which unit you choose.
Not directly. Break the shape into the supported shapes, calculate each, and sum the results.
The triangle mode takes a base and height, computes the area as one-half base times height, and derives the hypotenuse to report the perimeter of a right triangle.
Every calculation runs locally in your browser. Your numbers and expressions are not transmitted or stored.