A hollow cylinder: the region between two coaxial cylinders. Outer radius R, inner radius r, height h.

Volume = πh(R² − r²). Same as annulus area times height.

Outer lateral + inner lateral + 2 annuli: 2πh(R + r) + 2π(R² − r²).

Online Tube Calculator

Calculate volume and surface area of a tube (hollow cylinder): outer radius R, inner r, height h.

Outer radius R

Inner radius r

Height h

Frequently Asked Questions

What is a tube?: A hollow cylinder: the region between two coaxial cylinders. Outer radius R, inner radius r, height h.
Volume formula?: Volume = πh(R² − r²). Same as annulus area times height.
Surface area?: Outer lateral + inner lateral + 2 annuli: 2πh(R + r) + 2π(R² − r²).

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