Introduction
Log scaling looks like pure arithmetic – measure twice, plug into a formula, done. In practice, the number you get out is only as good as the judgment behind the measurements: where on the log you measure, which end you trust, which scale the buyer will use, and what the formulas silently assume about the wood. The tips below are the practical habits that keep estimates honest, whether you are selling a few backyard logs or tallying a landing full of timber.
The Log Board Feet Calculator runs the Doyle, Scribner, and International 1/4-inch formulas from diameter and length, so the math is handled. These tips cover everything the calculator cannot: measuring technique, scale selection, buying and selling tactics, and milling decisions. Pair them with the complete guide for the full background on each rule.
Measuring Tips
Measure the small end, inside the bark – every time
All three scales are defined on the small-end diameter inside the bark. Measure at the narrow end of the log, and press the tape through the bark to the wood or subtract bark thickness (typically 0.5 to 1 inch total, or 1 to 2.5 cm, depending on species). A diameter tape – which reads diameter directly from circumference – is the traditional tool; a standard tape around the log divided by 3.1416 works just as well.
Average oval logs
Logs are rarely perfect circles. Measure the widest and narrowest diameters at the small end and average them: a log measuring 17 by 15 inches (43 by 38 cm) scales as a 16-inch log. Using only the wide reading inflates the estimate; using only the narrow one shortchanges the seller. The average is the fair number both sides can defend.
Measure length to the shortest side
Log ends are seldom cut square. Measure length along the shortest side of the log – that is the usable length the mill can actually saw. Standard practice adds a few inches of trim allowance beyond the nominal length (a “12-foot” log is often cut 12 ft 4 in, or 3.76 m), but the calculator wants the nominal footage: 12, not 12.33. More on field technique in the estimating guide.
Re-measure anything that looks odd
If one log in a tally reads dramatically higher or lower than its neighbors, measure it again before questioning the formula. Nine times out of ten the tape slipped, the bark was included, or the wrong end was measured.
Scale Selection Tips
Match the scale to your market, not your preference
Eastern US hardwood trade runs on Doyle; western softwood runs on Scribner; government and many professional sales use International 1/4-inch. Using a different scale than your buyer does not make your number wrong, but it makes it irrelevant to the negotiation. Ask which rule the price assumes before you scale a single log.
Know the Doyle discount on small wood
On 10 to 14-inch (25 to 36 cm) logs, Doyle reads 25 to 35 percent below Scribner and International. If a buyer quotes Doyle on small-diameter logs, either negotiate the per-MBF price upward to compensate or insist on Scribner or International. The formula-explained guide shows the divergence diameter by diameter.
Run all three and report the spread
When selling, present the tally under all three scales. It costs nothing, demonstrates you have done your homework, and frames the negotiation around which rule applies rather than whether your numbers are real.
Buying and Selling Tips
Scale it yourself before agreeing to anything
Never accept a buyer’s tally without an independent scaling. Walk the log deck with a tape, record diameter and length per log, and run the numbers through the calculator. Discrepancies of 5 percent are normal measurement noise; discrepancies of 15 percent deserve a joint re-measurement.
Grade before you price
The formulas assume sound, straight logs. Before negotiating, check each log for the value-killers: center rot (sound the log with a hammer – a dull thud means decay), sweep (sideways curve), large knots, splits from felling, and embedded metal (nails, fence wire, bullets – all common in yard trees). One nail can destroy a $100 saw blade, and mills discount accordingly. Defect evaluation is covered in the material guide.
Sort by species and size
Mixed decks get mixed prices – usually the price of the cheapest log in the pile. Sorting walnut away from poplar, and 20-inch logs away from 12-inch logs, lets each group earn its own rate. An hour of sorting routinely pays for itself many times over.
Get two quotes on premium species
Walnut, cherry, and white oak have specialty buyers who pay for figure and veneer potential far above commodity log prices. A commodity mill’s quote is a floor, not a ceiling – a second quote from a specialty buyer is always worth the phone call.
Milling Tips
Remember what the scale assumes about kerf
The International rule assumes a 1/4-inch kerf; a thin-kerf portable band mill (around 1/8 inch, or 3 mm) actually recovers more lumber than any of the three scales predict, while a chainsaw mill (around 3/8 inch, or 9.5 mm) recovers less. If you mill with a thin-kerf band mill, expect to beat the scaled volume by 10 to 20 percent on straight logs – a quiet bonus the formulas do not advertise.
Saw for grade, not just volume
Board feet are not all equal: a wide, clear 8/4 walnut board is worth multiples of narrow common lumber from the same log. Plan the sawing pattern around the best boards the log can produce – live-sawing everything into 4/4 maximizes volume but can minimize value. Decide the product mix before the first cut.
Count drying time in the economics
Fresh-sawn lumber needs 6 to 12 months of air drying (longer for thick stock) before it is usable for most projects. That waiting period ties up space and delays revenue – factor it in before comparing milling income against a quick log sale. The tradeoff is examined in the DIY vs pro guide.
Metric Tips
Working in metric? Convert at the tape, not in your head: divide centimeters by 2.54 for the diameter in inches, and meters by 0.3048 for length in feet. Record both the metric measurement and the converted input on your tally sheet so either party can audit the numbers. To report results in cubic meters, multiply board feet by 0.0023597 – and note which scale the cubic meters derive from, since the scale spread carries through the conversion.
Related Guides
- Complete Guide – log board feet basics, the three scales, and a full worked example.
- Estimating Guide – how to measure diameter and length accurately in the field.
- Common Mistakes – the errors that distort scale results, with fixes.
- Cost Guide – typical log prices per MBF and what moves them up or down.
- Material Guide – species, quality, and defect deductions that affect value.
- Checklist – everything to verify before you buy, scale, or mill a log.
Frequently Asked Questions
What is the single most important log-scaling tip?
Measure the small-end diameter inside the bark. Wrong end or bark included are the two errors behind most disputed tallies.
How do I handle logs that are not round?
Measure the widest and narrowest diameters at the small end and average them. That average is the diameter to enter in the calculator.
Which scale favors the seller of small logs?
Scribner or International 1/4-inch. Doyle’s fixed 4-inch deduction penalizes logs under about 16 inches heavily – always confirm which rule a buyer’s quote assumes.
Should I trust the buyer’s tally sheet?
Verify it independently. Walk the deck, scale each log yourself, and compare. Small differences are normal; large ones deserve a joint re-measurement.
Does a thin-kerf mill really beat the scale?
Yes, often by 10 to 20 percent on straight logs. The scales assume standard kerfs; a thin-kerf band mill wastes less wood per cut and the bonus shows up in the lumber pile.
How long does milled lumber need to dry?
Typically 6 to 12 months of air drying for 4/4 stock, longer for thicker boards – roughly one year per inch of thickness is the traditional rule of thumb. Factor the wait into any milling decision.
Get Your Number
Good scaling is a habit, not a talent: measure the small end inside the bark, average oval logs, match the scale to the market, grade before pricing, and verify every tally independently. The Log Board Feet Calculator turns clean measurements into trustworthy numbers across all three rules. Take it to the log deck, run every log, and negotiate from knowledge instead of hope.
Disclaimer: Calculator results are planning estimates based on the dimensions you enter. Actual lumber recovery varies with species, log quality, defects, sawing method, and kerf. Verify volumes with your buyer, mill, or a professional scaler, and consult qualified professionals for timber-sale or structural decisions.
