Geometry Calculators
Last updated: October 2026
Triangle Area Calculator
Calculates the area of any triangle from two sides and the included angle (the SAS formula): A = ½·a·b·sin(C).
Circle Area Calculator
Calculate the area of a circle from its radius with A = πr², with the diameter and circumference shown alongside.
Regular Polygon Area Calculator
Calculate the area, perimeter, and interior angles of any regular polygon — from equilateral triangles to dodecagons — given just the side length.
Prism Calculator
Find the volume, total surface area, or lateral surface area of any prism — triangular, rectangular, or polygonal — from its base dimensions and height.
Circle Calculator
Enter any one circle measurement, radius, diameter, circumference or area, and get any other.
Sphere Calculator
Find a sphere's volume, surface area, radius or diameter from any one of those measurements.
Cylinder Surface Area and Volume Calculator
Compute the volume, lateral area, or total surface area of solid, hollow, or open-top cylinders.
Rectangle and Square Calculator
Find the area, perimeter, diagonal or aspect ratio of a rectangle or square from its length and width.
Ellipse Area and Circumference Calculator
Calculate the area, circumference (perimeter), eccentricity, and focal distance of an ellipse using its semi-major and semi-minor axes.
Cone Calculator
Compute the volume, lateral surface area, total surface area, or slant height of a right circular cone from its base radius and height.
Rectangular Prism Calculator
Calculate the volume, surface area, and space diagonal of a rectangular prism (box) from its length, width, and height.
Regular Polygon Calculator
Instantly calculate interior angles, exterior angles, area, and perimeter of any regular polygon.
Pythagorean Theorem Calculator
Solve a right triangle with a² + b² = c².