GlenCalc

Log board feet calculator

Measure the diameter inside the bark at the small end of the log. The three log rules give different answers, especially for small logs, so check which one your buyer or mill uses.

Your answer

International 1/4-inch rule181 board feet
Doyle rule144 board feet
Scribner (formula)166 board feet

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How we worked it out

Updated as you change the numbers.

  1. Doyle = ((D − 4) ÷ 4)² × L. Scribner ≈ (0.79D² − 2D − 4) × L ÷ 16. International 1/4 uses Grosenbaugh’s formula for the whole log length.

Method and assumptions

The International 1/4-inch rule comes closest to the lumber a modern mill actually saws. Doyle under-scales small logs heavily, which buyers in some regions still use. Scribner here is the formula version; official Scribner Decimal C tables round differently.

Questions

How many board feet in a 16 in × 16 ft log?

About 181 by the International 1/4-inch rule (the published table says 180), 144 by Doyle.

Sources

Method and figures checked on . Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.

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