Free Geometry Calculators

Area Calculator — 11 Shapes with Formulas & Perimeter

Calculate area and perimeter for 11 shapes: rectangle, square, circle, triangle, right triangle, trapezoid, parallelogram, rhombus, ellipse, hexagon, and sector. Formulas shown with your values substituted in.

Volume Calculator — 3D Shapes

Calculate the volume of cubes, spheres, cylinders, cones, and other 3D shapes.

Perimeter Calculator — 2D Shapes

Calculate the perimeter and circumference of common 2D shapes.

Pythagorean Theorem Calculator

Find the missing side of a right triangle using a² + b² = c².

Distance Calculator — 2D & 3D Points

Find Euclidean, Manhattan, and Chebyshev distance between 2D or 3D points. Includes midpoint, slope, line equation, and SVG visualization.

Midpoint Calculator — Two Points

Find the midpoint between two points in 2D or 3D coordinate space.

Slope Calculator — Gradient & Line

Calculate the slope of a line between two points and find the line equation.

Circle Calculator — Area & Circumference

Calculate radius, diameter, circumference, and area of a circle from any known value. Supports sector angle input for arc length, sector area, chord length, and segment area. Includes 7 unit options, adjustable precision, SVG diagram, and 5 real-world presets.

Surface Area Calculator — 3D Shapes

Calculate surface area of cubes, spheres, cylinders, cones, and other 3D shapes.

Triangle Solver — Law of Sines & Cosines

Solve any triangle given SSS, SAS, ASA, or AAS using law of sines and cosines.

Coordinate Geometry Calculator — Distance & Slope

Calculate distance, midpoint, slope, line equation, angle, section point, and triangle area from coordinates. Includes an interactive coordinate plane diagram, triangle analysis (centroid, inradius, circumradius), and step-by-step working.

Ellipse Calculator — Area, Perimeter & Eccentricity

Calculate the area, perimeter (Ramanujan II), eccentricity, focal distance, semi-latus rectum, directrix, flattening, and standard equation of any ellipse from its semi-axes.

Regular Polygon Calculator

Calculate the area, perimeter, interior angles, and diagonal of any regular polygon.

Heron's Formula Calculator — Triangle Area & Angles

Calculate triangle area using Heron's formula (SSS), SAS, or base-height. Shows all angles via law of cosines, altitudes, triangle type, SVG diagram, and step-by-step working.

Circle Sector Calculator — Arc, Area & Chord

Calculate arc length, sector area, chord length, segment area, and perimeter of a circle sector. Supports 4 solve-for modes (r+θ, arc+θ, area+θ, r+arc), degrees or radians, 7 length units, SVG diagram, presets, and step-by-step working.

Torus Calculator — Volume & Surface Area

Calculate the volume, surface area, and other properties of a torus (donut shape).

Golden Ratio Calculator — φ = 1.618033…

Calculate golden ratio dimensions from any measurement. Find A from B, B from A, total length, golden rectangle dimensions. Shows Fibonacci spiral convergence to φ with up to 15 decimal precision.

Frustum Calculator — Volume, Area & Slant Height

Calculate volume, slant height, lateral area, and total surface area of a frustum (truncated cone). Supports 5 units, 6 presets, SVG diagram, and step-by-step working.

Aspect Ratio Calculator — Screen & Image

Calculate aspect ratios, scale dimensions proportionally, and batch-resize images or videos without distortion.

Map Scale Calculator

Convert between map distances and real-world distances using any map scale ratio.

Paint Calculator — Gallons Needed for Walls & Ceilings

Calculate exactly how much paint you need for any room. Enter wall dimensions, doors, windows, and number of coats. Supports walls, ceilings, trims, and exterior surfaces with waste factor.

Flooring Calculator — Square Footage & Materials

Calculate flooring materials for any room shape. Enter dimensions, choose flooring type (hardwood, tile, vinyl, carpet), set waste factor, and get total square footage, boxes needed, and cost estimate.