Log volume: Huber and Smalian

A round log is traded by volume. Two common formulas give the solid volume from diameter and length.

Huber uses the diameter in the middle: V = π/4 × d² × L.

Smalian averages both end areas: V = π/8 × (d₁² + d₂²) × L.

Work in metres inside the formula. A log with a middle diameter of 30 cm (0.30 m) and a length of 4 m has V = 0.7854 × 0.09 × 4 = 0.283 m³.

Diameters are normally measured under bark, and the contract may prescribe another scaling rule. Defects such as sweep or rot are not included in the formula.