Geometry Calculator

Area, perimeter, volume & surface area for 12 shapes — with unit conversion and formula display.

Unit
Formula
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Select a shape, enter values and calculate

Free Online Geometry Calculator

Calculate area, perimeter, circumference, volume and surface area for 12 common shapes instantly. Built for students, teachers, engineers and construction professionals — no formulas to memorize, just enter your values.

Supported Shapes & Formulas

ShapeCalculationFormula
SquareArea
RectangleAreal × w
TriangleArea½ × b × h
CircleAreaπ × r²
EllipseAreaπ × a × b
TrapezoidArea½ × (a + b) × h
SphereVolume⁴⁄₃ × π × r³
CylinderVolumeπ × r² × h
ConeVolume⅓ × π × r² × h
CubeSurface Area6 × a²

Who Uses This Tool?

This geometry calculator is used by school and university students for homework and exam prep, teachers for quick formula verification, civil engineers for area estimation, interior designers for room planning, and developers needing quick geometry checks.

Frequently Asked Questions

Is this geometry calculator free?
Yes — completely free, no account needed, no watermarks, no limits.
Which shapes does it support?
Square, rectangle, triangle, circle, ellipse, trapezoid, parallelogram, rhombus (2D) and cube, cuboid, sphere, cylinder, cone (3D) — 13 shapes in total.
Can I change measurement units?
Yes. Choose from mm, cm, m, km, inches, feet and yards. The result unit updates automatically.
How is the triangle area calculated?
Using the standard formula: ½ × base × height. Enter the base and perpendicular height of the triangle.
Does it work on mobile?
Yes — fully responsive on phones, tablets and desktops.