Math Calculators

Torus Volume Calculator

Calculate the volume and surface area of a torus (donut shape) from its major and minor radii, with independent unit choices for each.

Major radius (R) — center to tube center

Minor radius (r) — tube radius

Volume unit

Surface area unit

Volume —

Surface area —

About the Torus Volume Calculator

A torus is a donut-shaped solid formed by revolving a circle of radius r around an axis at distance R from the circle's center. Its volume and surface area follow directly from Pappus's theorems. The major and minor radii each have their own unit selector, and so does every result — the calculator converts everything automatically.

Formulas: Volume = 2π²Rr² · Surface Area = 4π²Rr

Tori appear in engineering (O-rings, tubing), architecture and mathematics.