Geometry Calculators
Calculate measurements of flat shapes and solids. Every tool states its formula, and you can add a unit so results are labelled in cm², ft³ and so on.
Units in geometry
If lengths are in centimeters, areas come out in square centimeters and volumes in cubic centimeters. Converting afterwards is where most mistakes happen: 1 m = 100 cm, but 1 m² = 10,000 cm² and 1 m³ = 1,000,000 cm³. When in doubt, convert every length to the same unit before calculating, or use the area and volume converters afterwards.
General tools
Choose a shape from a list.
- Area CalculatorArea of rectangles, triangles, circles, trapezoids, sectors, polygons and more.
- Perimeter CalculatorPerimeter of polygons and circumference of circles and ellipses.
- Volume CalculatorVolume of cubes, boxes, cylinders, spheres, hemispheres, cones and pyramids.
- Surface Area CalculatorTotal and lateral surface area of common 3D solids.
2D shapes
- Rectangle CalculatorArea, perimeter and diagonal of a rectangle from its length and width.
- Square CalculatorKnow one measurement of a square? Get all the others.
- Circle CalculatorFind radius, diameter, circumference and area from any one of them.
- Triangle CalculatorSolve any triangle from SSS, SAS, ASA or AAS: all sides, angles and area.
- Pythagorean TheoremFind the missing side of a right triangle from the other two.
- Trapezoid CalculatorArea, median and perimeter of a trapezoid (trapezium).
- Parallelogram CalculatorArea, perimeter and interior angles of a parallelogram.
- Rhombus CalculatorArea, side length, perimeter and angles of a rhombus from its diagonals.
3D solids
- Cube CalculatorEdge, volume, surface area and diagonals of a cube from any one value.
- Box / Rectangular PrismVolume, surface area and diagonal of a box (cuboid).
- Cylinder CalculatorVolume, surface area and capacity of a cylinder.
- Sphere CalculatorVolume, surface area, radius and diameter of a sphere from any one value.
- Cone CalculatorVolume, slant height and surface area of a right circular cone.