Example 01
Six walnut shelf boards
1 in thick, 8 in wide, 3 ft long. Quantity: 6.
Walk-through
(1 × 8 × 36 × 6) ÷ 144 = 12 board feet
Result 12 BF
Calculators · 03 of 05
Board Feet Calculator.
Build a cut list and get the total in board feet. Add a price per board foot and the calculator estimates your lumber cost. Works for rough-sawn, surfaced, or dimensional stock.
- Imperial & metric
- Cut list entry
- Price estimate
- Shareable URL
The formula
How board feet are calculated
A board foot is a unit of volume: 1 inch thick, 12 inches wide, 12 inches long. The formula converts your actual dimensions into that unit so you can price lumber consistently.
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Enter dimensions
Thickness and width in inches, length in feet. For each piece in your cut list, add a row.
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Set quantity
How many identical pieces you need of this size.
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Calculate
The calculator multiplies thickness × width × length (converted to inches) × quantity, then divides by 144.
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Price (optional)
Enter a price per board foot. The calculator multiplies total board feet by the price.
Worked examples
Three cut lists
Different projects, same formula.
Example 02
A tabletop from 8/4 cherry
2 in thick (8/4), 6 in wide, 8 ft long. Quantity: 5 boards edge-glued.
Walk-through
(2 × 6 × 96 × 5) ÷ 144 = 40 board feet
Result 40 BF
Example 03
Mixed cut list with pricing
Two sizes of white oak at $9.50/BF: four pieces at 1 × 4 × 6 ft and two pieces at 1 × 6 × 4 ft.
Walk-through
Row 1: (1 × 4 × 72 × 4) ÷ 144 = 8 BF
Row 2: (1 × 6 × 48 × 2) ÷ 144 = 4 BF
Total: 12 BF × $9.50=$114.00
Result 12 BF, estimated cost $114.00
When you'd use this
Five reasons to calculate board feet
Any time you are buying lumber priced by the board foot.
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Furniture projects
Estimate how much hardwood you need for a table, shelf, or cabinet and what it will cost before you order.
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Comparing suppliers
Price per board foot lets you compare quotes from different mills on equal footing.
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Rough-sawn purchasing
Mills sell rough lumber by the board foot. Know your total before you drive out to pick boards.
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Job bidding
Contractors include a material line item in proposals. Board feet times cost per BF gives a defensible number.
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Waste planning
Add 15 to 20 percent to your cut list total for defects, end checks, and saw kerf. Better to return lumber than to make a second trip.
Conversion reference
| Nominal size | Board feet per linear foot | Board feet per 8 ft board |
|---|---|---|
| 1 × 4 | 0.33 | 2.67 |
| 1 × 6 | 0.50 | 4.00 |
| 1 × 8 | 0.67 | 5.33 |
| 1 × 10 | 0.83 | 6.67 |
| 1 × 12 | 1.00 | 8.00 |
| 2 × 6 (8/4) | 1.00 | 8.00 |
Frequently asked
Board feet questions
Common questions about buying lumber by the board foot.
What is a board foot?
A board foot is a unit of volume equal to a piece of wood 1 inch thick, 12 inches wide, and 12 inches long (144 cubic inches). It is the standard pricing unit for hardwood lumber in North America.
Do I use nominal or actual dimensions?
For pricing, use nominal dimensions. A "1-inch" board is priced as 1 inch even if it has been surfaced to 3/4 inch. If you are calculating how much wood you will actually have after surfacing, use actual dimensions.
What does 4/4, 8/4, etc. mean?
These are quarter-inch thickness designations. 4/4 = 1 inch (four quarters), 8/4 = 2 inches, 6/4 = 1.5 inches. The number before the slash is how many quarter inches thick the board is in its rough-sawn state.
How much extra should I buy for waste?
A common rule of thumb is 15 to 20 percent. This covers saw kerf, end checks, knots you cut around, and pieces that do not make the grade. For high-value species or tight-grained wood, some woodworkers plan for 10 percent.