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/// Lumber volume measure

Board Foot Calculator

Use the board foot calculator to multiply entered thickness, width, length, and piece quantity, divide by twelve, and apply your allowance. Enter dimensions on the same basis used by the seller because nominal, rough, and dressed sizes may differ. Board feet describe lumber volume, not structural capacity, grade, usable cut yield, or piece count.

Content reviewed Jul 16, 2026 · Source records reviewed through Jul 15, 2026

01

Lumber dimensions and quantity

Enter the dimensions used by the seller. Rough, nominal, and dressed lumber dimensions may not describe the same volume.

inExample starting value — replace it with the project or product value.
inExample starting value — replace it with the project or product value.
ftExample starting value — replace it with the project or product value.
piecesExample starting value — replace it with the project or product value.
%Required — enter a project-specific planning value and verify it before ordering. ProjectQty does not apply an unsupported default.
USDOptional — enter your current local price per board foot.
View current estimate

/// Answer-first planning notes

How many board feet are represented by my lumber dimensions?

How many board feet are represented by my lumber dimensions checkpoints
Planning inputCalculation roleProject check
Thickness and widthSet cross-sectional lumber volumeMatch seller pricing dimensions
Length and quantityScale volume across piecesGroup identical sizes only
AllowanceAdds explicit defect or cutting volumePlan actual cuts separately
Source-backed fact

One board foot is the volume of a board one inch thick, twelve inches wide, and one foot long.

Evidence: USDA Forest Service, Pacific Northwest Research Station

/// Formula & field notes

How this board foot estimate works

FormulaBoard feet = thickness in inches × width in inches × length in feet ÷ 12 × quantity × (1 + waste %).

Worked example

Ten pieces measuring 2 in × 6 in × 8 ft contain 80 board feet before any defect or cutting allowance.

/// Source trail

Data & assumptions

Every source has a declared scope. A reference can support a conversion or product assumption without turning this estimate into a supplier quote.

National Institute of Standards and Technology · Primary evidenceNIST Guide to the SI, Appendix B: Conversion Factors

Exact international-foot to meter conversion; U.S. survey-foot conversion is explicitly outside this claim.

Effective 2025-08-18 · Reviewed 2026-07-15 · Next review 2027-07-15
NOAA National Geodetic Survey · Prequalified fallbackThe DSDATA Format, Appendix D: U.S. Survey Foot vs International Foot

Independent confirmation that one international foot equals exactly 0.3048 meters; U.S. survey-foot conversion remains distinct.

Effective 2025-06-10 · Reviewed 2026-07-15 · Next review 2027-07-15
Department of Justice Canada · Primary evidenceSoftwood Lumber Products Export Charge Act: board-foot definition

Nominal board-foot definition for lumber; log-scale recovery conversions are outside this claim.

Effective 2026-05-26 · Reviewed 2026-07-15 · Next review 2027-07-15
USDA Forest Service, Pacific Northwest Research Station · Prequalified fallbackUSDA Forest Service PPET units: board-foot definition

Independent nominal board-foot definition for lumber; empirical log-scale conversion factors are excluded.

Effective 2025-07-22 · Reviewed 2026-07-15 · Next review 2027-07-15

/// Common questions

Board Foot calculator FAQ

What should I verify before ordering lumber?

Confirm field dimensions and actual versus nominal dimensions and seller pricing basis against the exact product or supplier information. ProjectQty shows the assumptions so you can replace planning defaults before ordering board feet.

How does waste affect the lumber estimate?

Waste is applied after the base geometry is calculated and before discrete packages or pieces are rounded up. Use a higher allowance for complex layouts, cuts, pattern matching, breakage, or uncertain field dimensions.

Is this lumber result a professional design?

No. It is a quantity-planning result. Species, grade, moisture, preservative treatment, span, connections, and structural suitability require the project specification.

/// Keep planning

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