Calculate board feet instantly for lumber buying and project planning.
Here’s a scenario every woodworker knows: You’re at the lumber yard, standing in front of a stack of beautiful walnut, trying to do mental gymnastics to figure out if 47 board feet is enough for your project. At the same time, the guy behind you sighs impatiently.
This calculator handles the math so you don’t have to. Enter your dimensions, add multiple pieces, and receive instant board footage with cost estimates.
No more napkin math. Just accurate board feet, every time.
🔧 Input Method
📐 Dimensional Lumber (Nominal)
🪓 Hardwood Thickness (Quarter System)
Dimension Type:
Nominal
Actual
📦 Lumber List
1
Lumber Piece
in
in
ft
pcs
Per Piece
8.00 BF
Subtotal
8.00 BF
Total Board Feet
8.00
board feet
Total Pieces
1
pieces
📏
Linear Feet
8
ft total
📐
Square Feet
8
sq ft (face)
📦
Cubic Feet
0.67
cu ft
➕
With 15% Waste
9.20
board feet
💰 Cost Estimation
Lumber Only
$64.00
With 15% Waste
$73.60
Estimated Total
$73.60
📝 Board Feet Formula
Board Feet = (Thickness” × Width” × Length’) ÷ 12
📖 How to Use This Calculator
1
Select Size
Choose a preset or enter custom dimensions
2
Set Quantity
Enter how many pieces you need
3
Add More Sizes
Add different lumber sizes for your project
4
Get Total & Cost
View board feet and cost estimate
📊 Board Feet Reference Charts
| Size | BF/Foot | 8′ Board | 10′ Board | 12′ Board |
|---|---|---|---|---|
| 1×4 | 0.33 | 2.67 BF | 3.33 BF | 4.00 BF |
| 1×6 | 0.50 | 4.00 BF | 5.00 BF | 6.00 BF |
| 1×8 | 0.67 | 5.33 BF | 6.67 BF | 8.00 BF |
| 1×10 | 0.83 | 6.67 BF | 8.33 BF | 10.00 BF |
| 1×12 | 1.00 | 8.00 BF | 10.00 BF | 12.00 BF |
| 2×4 | 0.67 | 5.33 BF | 6.67 BF | 8.00 BF |
| 2×6 | 1.00 | 8.00 BF | 10.00 BF | 12.00 BF |
| 2×8 | 1.33 | 10.67 BF | 13.33 BF | 16.00 BF |
| 2×10 | 1.67 | 13.33 BF | 16.67 BF | 20.00 BF |
| 2×12 | 2.00 | 16.00 BF | 20.00 BF | 24.00 BF |
| Species | $/BF Range | 10 BF | 50 BF | 100 BF |
|---|---|---|---|---|
| Poplar | $3-5 | $30-50 | $150-250 | $300-500 |
| Soft Maple | $4-6 | $40-60 | $200-300 | $400-600 |
| Red Oak | $5-8 | $50-80 | $250-400 | $500-800 |
| Hard Maple | $6-10 | $60-100 | $300-500 | $600-1,000 |
| Cherry | $7-12 | $70-120 | $350-600 | $700-1,200 |
| White Oak | $7-12 | $70-120 | $350-600 | $700-1,200 |
| Walnut | $10-18 | $100-180 | $500-900 | $1,000-1,800 |
| Exotic | $15-50+ | $150-500+ | $750-2,500+ | $1,500-5,000+ |
| Nominal | Actual (Dry) | Thickness | Common Use |
|---|---|---|---|
| 1×4 | ¾” × 3½” | 0.75″ | Trim, crafts |
| 1×6 | ¾” × 5½” | 0.75″ | Shelving, panels |
| 1×8 | ¾” × 7¼” | 0.75″ | Shelving, siding |
| 1×12 | ¾” × 11¼” | 0.75″ | Wide boards, shelves |
| 2×4 | 1½” × 3½” | 1.50″ | Framing, structure |
| 2×6 | 1½” × 5½” | 1.50″ | Framing, decks |
| 4/4 Hardwood | 13/16″ surfaced | ~0.81″ | Furniture, cabinets |
| 5/4 Hardwood | 1-1/16″ surfaced | ~1.06″ | Tabletops, trim |
| 8/4 Hardwood | 1-13/16″ surfaced | ~1.81″ | Legs, thick stock |
📏 Nominal vs. Actual
Lumber is sold by “nominal” dimensions but measures smaller after drying and planing:
- A “2×4″ actually measures 1½” × 3½”
- A “1×6″ actually measures ¾” × 5½”
- Rough-sawn hardwood uses full nominal thickness
🪓 Quarter System
Hardwood thickness is measured in “quarters” of an inch:
- 4/4 = 1″ thick (four quarters)
- 5/4 = 1¼” thick
- 6/4 = 1½” thick
- 8/4 = 2″ thick
💡 Buying Tips
- Add 15-25% extra for waste and mistakes
- Rough-sawn is cheaper but needs planing
- Ask if prices are for rough or surfaced
- Wider boards often cost more per BF
- Check both ends for cracks before buying
❓ Frequently Asked Questions
How do you calculate board feet?
Use the formula: Board Feet = (Thickness × Width × Length) ÷ 144 when all measurements are in inches. Or use (Thickness” × Width” × Length in feet) ÷ 12. For example, a 2″ × 8″ × 10′ board = (2 × 8 × 10) ÷ 12 = 13.33 board feet.
What’s the difference between nominal and actual lumber dimensions?
Nominal is the lumber’s name size; actual is its real measurement after drying and planing. A “2×4″ nominally is actually 1.5″ × 3.5” when dry. For board feet calculations at lumber yards, they typically use nominal thickness for rough-sawn lumber — always confirm their policy.
How many board feet are in a 2×4×8?
Using nominal dimensions (2″ × 4″ × 8′), the calculation is (2 × 4 × 8) ÷ 12 = 5.33 board feet. However, note that 2×4s are typically sold by the piece or linear foot at home centers, not by board feet.
Why is hardwood sold by the board foot?
Hardwood comes in random widths and lengths, making per-piece pricing impractical. Board feet standardizes pricing regardless of board dimensions, allowing fair value comparison across different sizes of lumber.
What does 4/4 lumber mean?
The fraction indicates thickness in quarters of an inch. 4/4 = 4 quarters = 1 inch thick (rough). 8/4 = 8 quarters = 2 inches thick. This refers to rough-sawn thickness before any surfacing, which removes some material.
How much extra lumber should I buy for waste?
Add 15-25% extra for waste, defects, and cutting errors. Use 15% for simple projects with straight cuts. Use 20-25% for complex projects with many cuts, figured wood that may have defects, or if you’re less experienced.
Do I calculate board feet using rough or finished thickness?
Most lumber yards charge based on rough (nominal) thickness. If you buy 4/4 lumber and have it surfaced to 3/4″, you typically pay for the full 1″ thickness. Always confirm pricing basis with your supplier before purchasing.
How do I convert linear feet to board feet?
Multiply linear feet by the board’s thickness and width (in inches), then divide by 12. For example, 10 linear feet of 1×6 lumber: (1 × 6 × 10) ÷ 12 = 5 board feet.
What’s the difference between a board foot and a linear foot?
A linear foot measures length only (12 inches of length). A board foot measures volume (a piece 1″ thick × 12″ wide × 12″ long = 144 cubic inches). They’re completely different units and shouldn’t be used interchangeably.
How many board feet are in a typical hardwood board?
Random-width hardwood typically ranges from 4-12″ wide and 6-16′ long. A common board might be 1″ × 6″ × 8′ = 4 board feet. But sizes vary significantly since hardwood is sold in random widths and lengths rather than uniform sizes.