Board Foot Calculator
This board foot calculator finds the board feet of lumber from the thickness, width, length, and number of boards. Enter the dimensions and the board foot calculator returns the total board feet, the unit lumber is priced and sold by. It handles the full board feet calculation for one board or a whole stack, so you can price and order hardwood without doing the bd feet math by hand.
Results
The Board Foot Calculator is part of our Materials Estimating collection. Browse more materials estimating to size, convert, and check your work alongside this tool.
What the board foot calculator does
A board foot is a volume of lumber, twelve inches square by one inch thick, and this board foot calculator finds how many are in your boards. Enter the thickness, width, and length and it runs the board feet calculation, then multiplies by the quantity for a stack. Because hardwood is sold by the board foot, the bd feet calculator turns a cut list into a price, which is why a board foot calculator lumber buyers rely on it before ordering.
The board foot calculation formula
The board foot calculation formula multiplies the three dimensions and divides by 144, since one board foot is 144 cubic inches:
When the length is in feet, the board foot calculator uses the shortcut of thickness times width times length-in-feet divided by 12. Either way the board feet calculation gives the same result, and the tool multiplies by the number of boards for the total the bd ft calculator reports.
Board feet calculation example
Ten boards, each 2 inches thick, 6 inches wide, and 8 feet long. The board foot calculation formula gives per board:
The board foot calculator returns 80 bd ft. At a cost of 5 dollars per board foot, a board feet price calculator would put the lumber at 400 dollars.
How to use the board foot calculator
Enter the board thickness in inches, the width in inches, and the length in feet, then the number of boards. The board foot calculator applies the board foot calculation formula and returns the total board feet. To price the order, note that a board feet price calculator simply multiplies the total by your cost per board foot, and this tool gives the board footage that figure needs.
Reading the board foot calculator result
The total board feet is what the lumberyard charges by, so it is your ordering and budgeting number. Remember that board feet measure nominal volume, not finished size: a board sold as 1 inch thick may be planed to less, yet it is still priced at the nominal board foot. For rough-sawn hardwood, order a little extra for planing and defects. The board foot calculator gives the nominal figure, which is exactly what a board foot calculator lumber suppliers quote against.
When to use the board foot calculator
- Pricing hardwood, where the board feet calculation sets the cost
- Estimating logs with a board feet calculator for logs
- Converting between area and volume with a board feet to square feet calculator
- Ordering by length using a linear board foot calculator
Common board foot calculator mistakes
- Using actual size. The board feet calculation uses nominal dimensions, not the planed size.
- Mixing units. Enter thickness and width in inches and length in feet so the board foot calculator applies the right divisor.
- Confusing linear and board feet. Linear feet ignore thickness and width; use board feet for solid lumber volume.
Tips for accurate results
- Use nominal thickness and width in the board foot calculator, not the dressed size.
- Add a little extra for planing and defects on rough-sawn stock.
- Multiply the total by your cost per board foot to price the order.
Why the board feet calculation uses nominal size
The commonest confusion with any board foot calculator is nominal versus actual size. Lumber is named by its rough-sawn dimension, so a 2 by 4 starts life at 2 by 4 inches but is planed to about 1.5 by 3.5 inches by the time you buy it. Board feet are always figured on the nominal size, because that is the volume of wood that was cut and what the mill prices against. This is why the board feet calculation for a 2 by 6 gives the same answer whether the board is rough or dressed. When you order, remember that a board foot is a billing unit, not a promise of finished dimensions.
Board feet calculation vs linear and square feet
Lumber gets measured three ways and mixing them causes ordering mistakes. Linear feet count length alone, ignoring thickness and width, which is fine for trim of a fixed profile but useless for pricing hardwood. Square feet cover area, used for sheet goods and flooring. Board feet capture volume, the right unit for solid lumber, which is why a board feet to square feet calculator and a linear board foot calculator exist to bridge between them. Use this board foot calculator for solid hardwood volume, and convert only when a supplier quotes in one of the other units.
Board foot calculator chart
Board feet per board for common lumber sizes, a quick board foot calculator chart:
| Nominal size | 8 ft | 10 ft | 12 ft |
|---|---|---|---|
| 1 × 4 | 2.67 | 3.33 | 4.00 |
| 1 × 6 | 4.00 | 5.00 | 6.00 |
| 2 × 4 | 5.33 | 6.67 | 8.00 |
| 2 × 6 | 8.00 | 10.0 | 12.0 |
| 2 × 8 | 10.7 | 13.3 | 16.0 |
Board Foot Calculator FAQ
How do I do a board feet calculation?
Multiply thickness in inches by width in inches by length in inches and divide by 144. The board foot calculator applies this board foot calculation formula and multiplies by the number of boards.
What is a board foot?
A board foot is 144 cubic inches of lumber, equal to a piece 12 inches square and 1 inch thick. The bd feet calculator reports how many your boards contain.
How do I price lumber by board foot?
Multiply the total board feet by your cost per board foot. This board foot calculator gives the total, and a board feet price calculator turns it into a cost.
Can it measure logs?
For sawn boards, yes. Logs use a log rule such as Doyle, so a dedicated board feet calculator for logs applies that rule; this tool covers dimensioned lumber.