What is a board foot?

A board foot is a volume measurement for lumber: 1 board foot = 144 cubic inches (12" × 12" × 1"). For example, a 2×4 that's 8 feet long is 5.33 board feet (2 × 4 × 8 ÷ 12 = 5.33).

How do I calculate board feet?

Formula: (Thickness in inches × Width in inches × Length in feet) ÷ 12 = board feet. For a 2" × 6" × 10': (2 × 6 × 10) ÷ 12 = 10 board feet. Note: use nominal dimensions, not actual.

Why is lumber priced by board foot?

Board foot pricing standardizes costs across different sizes. A 2×4 and a 1×8 of the same length contain different amounts of wood. Board foot pricing ensures fair comparison—you pay for actual wood volume.

What's the difference between nominal and actual lumber sizes?

Nominal size is how lumber is sold (2×4, 4×4). Actual size is smaller after drying and planing: a 2×4 is actually 1.5" × 3.5". Use nominal dimensions for board foot calculations and pricing, actual for fit and spacing.

How much does lumber cost per board foot?

Prices vary widely: Pine/SPF: $1-3/bf, Hardwoods: $3-15/bf (oak, maple, walnut), Exotic woods: $10-40+/bf. Prices fluctuate with market conditions. Buying in bulk or rough-cut saves money versus finished dimensional lumber.

Home & Construction

Board Foot Calculator

Calculate board feet volume for lumber and estimate costs.

Thickness (in)

Width (in)

Length (ft)

Quantity

Price per Board Foot ($)

Enter lumber dimensions

How to Use This Calculator

Measure Lumber Dimensions

Note the thickness, width (both in inches), and length (in feet) of your lumber. Use nominal dimensions (how it's labeled) not actual dimensions for standard calculations.

Enter Measurements

Input thickness, width, and length into the calculator. For multiple pieces of same size, enter quantity. The calculator computes board feet for the total.

Calculate Board Feet

The calculator shows total board feet using the formula: (T × W × L) ÷ 12. This is the standard unit for pricing and ordering lumber, especially hardwoods.

Estimate Cost

Multiply board feet by price per board foot (check with lumber supplier for current rates). Add 10-15% waste for cuts and defects. Compare prices across suppliers using board foot pricing.