Board Feet Calculator
Calculate board feet for your lumber order and get instant cost estimates by wood species. Essential for furniture makers, woodworkers, and DIYers buying hardwood lumber.
Furniture project, ~10 BF
Estimated Cost
$32 – $64
$4.00 – $8.00 per board foot
Board Feet (Total)
8.0 BF
Per Piece
4.00 BF
Cost Per Piece
$16.00–$32.00
Linear Feet
16 LF
Red Oak: Popular hardwood with prominent grain. Classic furniture wood. Hard (1,290 Janka).
Hardwood Notation: 4/4 = 1", 5/4 = 1.25", 6/4 = 1.5", 8/4 = 2" (rough thickness before milling). Final thickness is ~1/8" less after surfacing.
Not included: Milling/surfacing ($0.25–$0.50/BF), waste/defects (order 15–20% extra), delivery, or project-specific hardware.
Lumber Cost by Species
| Wood Species | Cost Per BF | Janka Hardness |
|---|---|---|
| Pine / SPF | $2–$5 | 380–690 (Soft) |
| Poplar | $3–$6 | 540 (Soft Hardwood) |
| Red Oak | $4–$8 | 1,290 (Hard) |
| White Oak | $5–$10 | 1,360 (Hard) |
| Hard Maple | $5–$10 | 1,450 (Very Hard) |
| Cherry | $6–$12 | 950 (Medium) |
| Black Walnut | $8–$16 | 1,010 (Medium) |
Nominal vs Actual Lumber Sizes
| Nominal Size | Actual Size | BF per 8ft |
|---|---|---|
| 1×4 | 3/4" × 3-1/2" | 2.67 (nominal) / 1.75 (actual) |
| 1×6 | 3/4" × 5-1/2" | 4.0 (nominal) / 2.75 (actual) |
| 2×4 | 1-1/2" × 3-1/2" | 5.33 (nominal) / 3.5 (actual) |
| 2×6 | 1-1/2" × 5-1/2" | 8.0 (nominal) / 5.5 (actual) |
| 2×10 | 1-1/2" × 9-1/4" | 13.33 (nominal) / 9.25 (actual) |
*Most lumber yards calculate board feet using nominal dimensions
How We Calculate
Board feet is the standard unit for measuring and pricing hardwood lumber. One board foot equals a piece of wood 12" × 12" × 1" (or equivalent volume).
Board Feet = (Thickness" × Width" × Length') ÷ 12
Example: 2" × 8" × 10' = (2 × 8 × 10) ÷ 12 = 13.33 BF
Understanding Quarter Notation
Hardwood thickness is measured in quarters of an inch: 4/4 = 1", 5/4 = 1.25", 6/4 = 1.5", 8/4 = 2". This refers to rough-sawn thickness before surfacing. After planing (S2S), expect to lose ~1/8".
Nominal vs Actual Dimensions
Dimensional lumber (2×4, 2×6, etc.) from home centers is smaller than the nominal size due to drying and surfacing. A 2×4 is actually 1.5" × 3.5". Hardwood from lumber yards is typically sold at rough or surfaced actual dimensions.
Waste Factor
When planning a project, add 15–20% extra for waste, defects, and cutting errors. Hardwood often has character (knots, grain variation) that may not suit every piece of your project.
Data Sources
Prices verified from specialty lumber yards, Rockler, Woodcraft, and hardwood dealers (February 2026). Prices vary significantly by region, grade, and market conditions. Walnut and cherry prices fluctuate more than oak and maple.
Frequently Asked Questions
How do you calculate board feet? +
Board feet = (Thickness × Width × Length) ÷ 12, where thickness and width are in inches, and length is in feet. For example, a 1" × 6" × 8' board = (1 × 6 × 8) ÷ 12 = 4 board feet.
How much does lumber cost per board foot? +
Lumber costs $2–$18 per board foot depending on species. Pine/SPF: $2–$5/BF. Red Oak: $4–$8/BF. Hard Maple: $5–$10/BF. Walnut: $8–$16/BF. Cherry: $6–$12/BF.
What does 4/4 lumber mean? +
4/4 means the lumber is approximately 1" thick (4 quarter-inches). 5/4 = 1.25", 6/4 = 1.5", 8/4 = 2". This is rough-sawn thickness — after surfacing, expect ~1/8" less.
Is a 2×4 actually 2 inches by 4 inches? +
No. A 2×4 is nominally 2" × 4" but actually measures 1.5" × 3.5" after drying and planing. This affects board feet calculations — use actual dimensions for accuracy.
How many board feet are in a 2×4×8? +
A 2×4×8 contains 5.33 board feet using nominal dimensions (2×4×8÷12), or 3.5 board feet using actual dimensions (1.5×3.5×8÷12). Lumber yards typically use nominal.
What is FAS lumber grade? +
FAS (First and Seconds) is the highest hardwood grade — clear wood with minimal defects. Lower grades include #1 Common (cabinet grade) and #2 Common (more knots, lower cost).
How much extra lumber should I buy? +
Buy 15–20% extra for furniture projects to account for defects, knots, and cutting waste. For construction lumber, 10% extra is usually sufficient.
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