Spike's Calculators

The hoppus foot is named for Edward Hoppus, who introduced this measurement in his manual of practical calculations, published in 1736.

*It is plain to the most casual observer that this is a most primitive system and that "Hoppus," whoever he might be, succeeded in attaching his name to it, not as its inventor, but merely as its tabulator, for his famous work is nothing but a ready-reckoner, compiled after the manner of the old road-books of the coaching days, for carrying in the pocket. (The Journal of the Society of Estate Clerks of Works, 1898).*

Hoppus feet are calculated at 78.5% of the cubic volume of a round log, allowing for 21.5% of waste.

- enter the length of the log in feet
- the circumference of the log at midlength in inches

- the volume of the log in Hoppus's feet
- the Hoppus feet converted to board feet
- log volume in cubic feet

V = (G ÷ 4)² * L ÷ 144

V = volume in Hoppus feet G = girth measured mid point of the log in inches L = length of log in feet

V = (G ÷ 4)² * L ÷ 113

one Hoppus foot (h ft) = 1.273239545 cubic feet (ft³) one Hoppus foot (h ft) = 15.27887454 board feet (bf)

- Brereton Log Rule - Metric Measurements
- Burt's Quarter Girth Method
- Chinese National Standard
- Cubic Metre Rule
- Francon Measure
- Hoppus Rule
- Huber's Formula
- Huber's Formula - Metric
- Ireland - Log Volume Measurement
- Japanese Agricultural Standard (JAS)
- Manitoba - Cubic Method
- Newton's Formula
- Nova Scotia Cubic Metre Log Scale
- Pressler's Cubic Foot Formula
- Smalian's Formula - Metric
- Smalian's Formula - Imperial
- Solid Volume of a Log
- Spike's Rule
- Swedish Log Volume Calculation
- Swedish Log Volume Calculation Method One
- Swedish Log Volume Calculation Method Two
- Swedish Log Volume Calculation Method Three
- William Klemme