How many board feet in a 20 in × 16 ft log?
A 20 in × 16 ft log scales about 290 board feet by International ¼-inch, 272 board feet by the Scribner formula and 256 board feet by Doyle.
How to work it out
- Doyle: (20 − 4)² × 16 ÷ 16 = 256 · Scribner: (0.79 × 20² − 2 × 20 − 4) × 16 ÷ 16 = 272
- International ¼″: 4 full 4 ft sections, diameter growing ½ in per section for taper, × 0.905 for kerf = 290
At 20 in the three rules start to converge, and by about 30 in Doyle catches up with International. Large, clear logs are where most of the lumber — and most of the log value — is concentrated.
Adjust for your project
More options: Price per MBF (optional)
- International ¼-inch
- 290 board feet
- Doyle
- 256 board feet
- Scribner (Bruce formula, ≈)
- 272 board feet
- Scribner Decimal C (published table, 16 ft logs)
- 280 board feet
- Solid volume (small-end cylinder)
- 34.9 cu ft
- These are gross figures for a sound, straight log. A scaler deducts for rot, sweep, crook, splits and metal to get the net scale you are paid on, and the extra length left for trimming (the trim allowance) is not counted.
A load of 20 in × 16 ft logs
| Number of logs | International ¼-inch | Scribner (Bruce formula, ≈) | Doyle | Solid volume (small-end cylinder) |
|---|---|---|---|---|
| 1 | 290 board feet | 272 board feet | 256 board feet | 34.9 cu ft |
| 3 | 869 board feet | 816 board feet | 768 board feet | 105 cu ft |
| 5 | 1,449 board feet | 1,360 board feet | 1,280 board feet | 175 cu ft |
| 10 | 2,898 board feet | 2,720 board feet | 2,560 board feet | 349 cu ft |
| 20 | 5,796 board feet | 5,440 board feet | 5,120 board feet | 698 cu ft |
What to know about a 20 in × 16 ft log
- The rules nearly agree. Doyle’s fixed 4 in slab allowance matters less as the log gets bigger, so here it is only about 12% under International. The published figures in Virginia Cooperative Extension 420-085 are 256 Doyle, 280 Scribner and 290 International.
- It is heavy. A 20 in × 16 ft log holds about 35 cubic feet of wood, which for most green hardwoods is well over a ton. Roll it with a cant hook or a tractor, not by hand.
- Grade matters more than volume. A straight, clear butt log this size can be worth far more per MBF than a knotty one of the same diameter. Log rules only measure volume; grade and defects set the price.
For comparison, board feet in a 16 in × 16 ft log is about 181 International, and board feet in a 12 in × 16 ft log only 97.
Different size? Use the full Log Board Foot Calculator.
What you’ll need
- Cant hook / log peaveyMid-range price
A long lever with a swinging hook for rolling and turning logs by hand — for measuring, bucking and loading without a tractor.
See options on Amazon (opens in a new tab) - Log scale stickBudget price
A graduated stick that reads board feet directly from a log’s small-end diameter. Check which rule it is printed for.
See options on Amazon (opens in a new tab) - 25 ft tape measureBudget price
A 25 ft tape with a stiff blade and a readable 1/16 in scale covers everything from cut lists to deck layout.
See options on Amazon (opens in a new tab)
As an Amazon Associate we earn from qualifying purchases. Links to products are affiliate links — they cost you nothing extra and help keep these calculators free.
Frequently asked questions
How many board feet in a 20 in × 12 ft log?
About 212 board feet International ¼-inch, 204 board feet Scribner and 192 board feet Doyle.
How many board feet in a 24 in × 16 ft log?
About 424 board feet International, 403 board feet Scribner and 400 board feet Doyle — the three rules are now within 6%.
How many board feet in ten 20 in × 16 ft logs?
About 2,898 board feet by International ¼-inch, 2,720 board feet by the Scribner formula and 2,560 board feet by Doyle.
Other common sizes
- Board feet in a 16 in × 16 ft log — 181 board feet
- Board feet in a 12 in × 16 ft log — 64 board feet
Sources
- Virginia Cooperative Extension, Forest Landowner’s Guide to the Measurement of Timber and Logs (publication 420-085) (opens in a new tab) — Doyle, Scribner and International ¼-inch rules; published board feet for 16 ft logs, including the Scribner Decimal C column used here; Doyle and Scribner underscale small logs.
- Briggs, D. — Forest Products Measurements and Conversion Factors, Chapter 2: Measurement of logs (University of Washington, College of Forest Resources) (opens in a new tab) — Gross vs net scale (defect deductions), trim allowance, and the Bruce and Schumacher formula BF = (0.79D² − 2D − 4) × L ÷ 16 as an approximation of Scribner.