Lumber Board Feet Calculator

Board-feet = (thickness in × width in × length ft) / 12 × pieces.

Inputs

Result

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General calculation reads

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How to use this calculator

  • Enter thickness, width, length, and count.
  • Use actual dimensions, not nominal.
  • Read total board feet.

About this calculator

A "board foot" is a volume measure: 1 inch thick × 12 inches wide × 12 inches long = 144 in³. The standard formula in lumber yards. Note: nominal vs actual size matters — a "2×4" is actually 1.5×3.5". Use ACTUAL dimensions for board feet.

Frequently asked

Nominal vs actual?+
"2×4" actual is 1.5×3.5 (after planing). For board-foot calculation, use actual. For lumber-yard pricing, often quoted in nominal — check.
Linear feet vs board feet?+
Linear feet measures length. Board feet measures volume. A 10' 2×4 is 10 LF but 6.67 BF.
Why does this matter?+
Hardwoods are usually priced per BF. Construction lumber (2×4, 2×6) is often per LF or per piece.
Surface measure (SM)?+
Common for hardwoods: thickness × width × length / 12, ignoring quantity. Different way to express the same volume.
How accurate is rough lumber?+
Rough/unsurfaced lumber sells at nominal; planed lumber at actual. Sometimes a charge difference applies.

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Annual conflict of interest disclosure form for nonprofit board members and key employees — IRS Form 990 Schedule L compliance.