How to use a lumber calculator for board feet and cost
Start with the dimensions on your quote. Enter Board thickness, Board width, Board length, Number of boards, and the cost figure, then choose Cost per board or Cost per board foot. The result keeps the entered dimensions beside their converted values, formula, assumptions, and totals.
Calculate board feet and lumber cost
- Choose Cost per board or Cost per board foot.
- Enter Board thickness, Board width, Board length, and Number of boards.
- Select the unit beside each dimension, then enter Cost per board ($) or Cost per board foot ($).
- Click Calculate.
- Use Copy result, Download result (.txt), or Reset after the calculation.
What the lumber calculator calculates
The calculator converts thickness and width to inches and length to feet before applying the board-feet formula. For one board, multiply thickness in inches by width in inches by length in feet, then divide by 12. Total board feet is that value multiplied by Number of boards.
Input: 1.5 in x 3.5 in x 8 ft, 10 boards, $6.50 per board
Board feet per board: 3.500
Total board feet: 35.000
Total cost: $65.00With Cost per board selected, total cost is the entered price multiplied by Number of boards. With Cost per board foot selected, the rate is multiplied by total board feet. The Result section also shows Board feet per board and Total linear length, plus the implied price in the other unit.
Lumber calculator units and input limits
- Board thickness and Board width accept
in,mm, orcm. Each is converted to inches before the formula runs. - Board length accepts
ft,in,m, orcmand is converted to feet. - Board thickness accepts
0.01to100; Board width accepts0.01to500; Board length accepts0.01to10,000. - Number of boards accepts whole numbers from
1to100,000. The selected cost input accepts0.01to1,000,000.
Blank, nonnumeric, non-finite, and out-of-range values show an error instead of a result. Number of boards must be a whole number. The calculator uses the dimensions you enter, so a nominal 2x4 stays nominal unless you enter its actual dressed dimensions yourself.
Where a lumber calculator comes up
- Enter the dimensions and count from a lumber quote to check the resulting board feet and total cost.
- Use Cost per board foot for a batch priced by board footage. The result keeps the converted dimensions and formula visible.
- Use Total linear length for a material takeoff, then keep the text with Copy result or Download result (.txt).
Choose the right construction calculator
Use the Construction Calculators category when the job involves a different material, dimension, or load estimate. The Construction Materials Calculator is the better choice when you want one calculator with 23 construction modes, including lumber. Use the Deck Calculator for a deck estimate based on deck dimensions, board size, joist spacing, and post spacing. Choose the Flooring Calculator when the inputs are floor area, plank or tile box coverage, roll size, and waste.
Frequently asked questions
What is the formula for calculating board feet?
The board-feet formula is (thickness in inches x width in inches x length in feet) / 12 for one board. Multiply that result by Number of boards for total board feet.
How do I calculate lumber cost per board?
Cost per board is the entered board price multiplied by Number of boards. Select Cost per board, enter Cost per board ($), and click Calculate.
Can I use millimeters or centimeters in the lumber calculator?
You can use millimeters or centimeters for Board thickness and Board width, and centimeters for Board length. Board length also accepts feet, inches, and meters, with each unit selected independently.
Does the lumber calculator convert a 2x4 to actual size?
The lumber calculator does not convert nominal sizes to actual dressed sizes. Enter the dimensions used for the supplier's pricing, such as 1.5 in by 3.5 in if those are the figures you need to price.
Does the lumber calculator send my inputs anywhere?
The calculation uses your values locally in the browser. It does not send calculator inputs to a server during calculation, and it does not fetch supplier prices or availability.