GEOMETRY TOOLKIT

Geometry calculators

28 free calculators with labelled diagrams, instant results, unit conversion and the formulas behind every answer.

2D Shapes

Area, perimeter and more for flat shapes12

CircleArea, circumference, radius and diameter Sector & ArcArc length, sector area, chord and segment Ring (Annulus)Area between two concentric circles EllipseArea, perimeter, eccentricity and foci SquareArea, perimeter, diagonal and circle radii RectangleArea, perimeter, diagonal and circumradius ParallelogramArea, perimeter, angles and diagonals RhombusArea, side, perimeter and angles from diagonals TrapezoidArea, median and perimeter TriangleArea, perimeter and angles from base/height or three sides Equilateral TriangleArea, height, perimeter and radii from one side Regular PolygonArea, apothem, radii and angles for any n-gon

3D Solids

Volume and surface area for solids10

CubeVolume, surface area and diagonals CuboidVolume, surface area and diagonal of a box SphereVolume, surface area and diameter HemisphereVolume, curved and total surface area CylinderVolume, lateral and total surface area ConeVolume, slant height and surface area Cone FrustumVolume, slant height and surface area Square PyramidVolume, slant height and surface area TorusVolume and surface area of a ring solid CapsuleVolume and surface area of a cylinder with hemisphere caps

Advanced Tools

Solvers and coordinate geometry6

Triangle SolverSolve any triangle from SSS, SAS, ASA, AAS or SSA PythagoreanFind the missing side of a right triangle Distance & SlopeBetween two points: distance, midpoint, slope and line equation Polygon AreaArea, perimeter and centroid from vertex coordinates Circle from 3 PointsCentre, radius and equation through three points Angles & TrigDegrees, radians, gradians, DMS and trig values

About the Geometry Calculators

Geometry calculators for students, engineers, makers and anyone who needs a quick, correct answer. There are 28 free tools covering 12 two-dimensional shapes, 10 three-dimensional solids and 6 advanced tools such as a triangle solver, coordinate geometry and polygon area from points.

Each calculator has a labelled diagram, instant results, unit conversion between metric and imperial lengths, and the formulas used. Everything runs in your browser, with no sign-up.

Geometry Calculators FAQ

Which geometry calculators are available?

2D Shapes: Circle, Sector & Arc, Ring (Annulus), Ellipse, Square, Rectangle, Parallelogram, Rhombus, Trapezoid, Triangle, Equilateral Triangle and Regular Polygon. 3D Solids: Cube, Cuboid, Sphere, Hemisphere, Cylinder, Cone, Cone Frustum, Square Pyramid, Torus and Capsule. Advanced Tools: Triangle Solver, Pythagorean, Distance & Slope, Polygon Area, Circle from 3 Points and Angles & Trig.

How do I calculate area and volume online?

Open the shape you need, enter its dimensions in one unit, and read the area, perimeter, volume or surface area. Results update as you type.

Are the geometry calculators free?

Yes, they are free, need no account, and your numbers never leave your device.