How it works
Find volume and surface area of a ring torus. The major radius measures from the centre of the hole to the centre of the tube.
V = 2π²Rr²; S = 4π²Rr
Worked example
Show example inputs and result
Major radius: 5 · Tube radius: 2.
- Volume
- 394.78417604
- Surface area
- 394.78417604
Questions and answers
Why are some results rounded?
Results display up to 8 decimal places. Calculations use the unrounded values; very small values use scientific notation. JavaScript floating-point arithmetic can introduce tiny rounding differences.
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The calculator processes inputs in your browser. Its code does not send your values to a server.
Method reviewed: October 8, 2026 · Methods & accuracy