Log Board Foot Calculator: Doyle, Scribner, and International Rules
Board Foot Calculator
Board foot = thickness (in) × width (in) × length (ft) ÷ 12. Enter nominal sizes as billed, or switch to actual measured sizes.
Estimate only. Species prices vary by yard, region and date. Confirm the final tally and price with your lumber supplier before ordering.
Logs are scaled with different rules, including Doyle, Scribner, and International 1/4 inch. The same log can scale differently under each rule, so buyer and seller must agree on the rule before money changes hands.
Doyle rule
Board feet = (diameter in inches – 4) squared x length in feet, divided by 16.
Worked example
A 12 inch diameter log, 16 feet long = (12 – 4) squared x 16 / 16 = 64 board feet. Doyle underestimates small logs and overestimates very large ones. Diameter is the small-end diameter inside the bark, and length is the merchantable length.
FAQ
Which rule should I use? Whichever you and the buyer or seller agree on, in writing, before the sale. Are log estimates exact? No, treat log estimates as estimates only.
Estimate only. Confirm with your supplier before ordering.