🍩 Torus Volume and Surface Area Calculator
Calculate the volume and surface area of a torus (donut shape) from its central radius and tube radius.
cm
cm
What this calculator finds
A torus is a donut-shaped surface formed by revolving a circle around an axis. This calculator finds its volume and surface area from two measurements: the central radius (distance from the torus’s center to the middle of the tube) and the tube radius (the radius of the circular cross-section).
The formula
Volume is V = 2π²Rr² and surface area is SA = 4π²Rr, where R is the central radius and r is the tube radius. These formulas assume a standard ring torus where R is greater than r.
This tool is useful for geometry, engineering, and design work involving ring-shaped objects such as gaskets, tires, and tubes. Results are for general estimation purposes.
Last reviewed August 2026