Board Foot Calculator
Work out board feet and cost from a board thickness, width, and length in feet or inches, across several board sizes, with cubic feet and cubic meters totals.
Length unit
Thickness and width are always in inches, the standard lumber convention. Length uses the unit picked here.
- 4 board feet each · 40 board feet total
Calculated in your browser. Nothing is uploaded.
Board feet are worked out as thickness in inches times width in inches times length in inches, divided by 144.
How to calculate board feet
Pick a length unit
Choose feet or inches for the length measurement. Thickness and width are always entered in inches.
Enter each board size
Type the thickness, width, length, and quantity for a board size. Add more rows for other sizes in the same order.
Set a price per board foot
Enter the price your supplier charges per board foot to see the total cost alongside the volume.
Read the totals
See the board feet for each size, the total board feet and cost across every row, and the equivalent in cubic feet and cubic meters.
Why use this tool
Board feet per board and in total
Each row shows the board feet for one board of that size, and the running total adds every row together as you fill them in.
Several board sizes at once
Add as many board sizes as an order needs, each with its own thickness, width, length, and quantity, and get one combined total.
Cost from a single price per board foot
Enter the price your supplier quotes per board foot and the total cost across every board size is worked out automatically.
Cubic feet and cubic meters included
Alongside the board foot total, see the same volume expressed in cubic feet and cubic meters, useful for comparing against other volume-based estimates.
Feet or inches for length
Switch the length unit between feet and inches to match how a board is measured, while thickness and width stay in the standard inch convention.
Runs entirely in your browser
Every calculation happens on your device as you type. Nothing is uploaded.
About this tool
A board foot is the standard unit for pricing rough lumber in the United States: one board foot is the volume of a board one inch thick, twelve inches wide, and twelve feet long, which works out to 144 cubic inches. This calculator applies that directly: thickness in inches times width in inches times length in inches, divided by 144, gives the board feet for one board. Multiply by how many identical boards you have and add up as many board sizes as an order needs to get a running total.
Length can be entered in feet, the common way lumber is sold, or in inches when working from an exact cut list; thickness and width stay in inches either way, since that is the standard convention for dimensioning lumber. Add a price per board foot and the tool multiplies it by the total to give a project cost, useful for comparing quotes or budgeting a build before placing an order. The total is also shown in cubic feet and cubic meters, since a board foot is one twelfth of a cubic foot, which is handy for cross-checking against a volume-based estimate elsewhere. For other material takeoffs, the tile calculator and the paint calculator cover flooring and wall coverage.
Treat the total as an estimate for ordering rough or dimensional lumber; it does not account for a mill’s minimum charges, grade premiums, or the extra length often added to a cut list for trimming. Everything is worked out on the page as you type, and nothing you enter is uploaded, stored, or logged.
Frequently asked questions
- What is a board foot?
- A board foot is a unit of lumber volume equal to a board one inch thick, twelve inches wide, and twelve feet long, or 144 cubic inches. Lumber yards price rough and dimensional lumber by the board foot rather than by the piece.
- How is board feet calculated?
- Multiply the thickness in inches by the width in inches by the length in inches, then divide by 144. If length is entered in feet, it is converted to inches first by multiplying by 12 before the same formula is applied.
- Why are thickness and width always in inches?
- Lumber is conventionally dimensioned in inches for thickness and width even when its length is sold in feet, since board thicknesses like three-quarters of an inch or a nominal two inches are the standard way mills describe stock.
- Can I calculate several board sizes at once?
- Yes. Add a row for each board size in an order, with its own thickness, width, length, and quantity. The tool totals the board feet and cost across every row you add.
- How is the cubic feet and cubic meters figure worked out?
- One board foot equals one twelfth of a cubic foot, since 144 cubic inches is a twelfth of the 1,728 cubic inches in a cubic foot. The total board feet is divided by twelve for cubic feet, then converted again for cubic meters.
- Is my data uploaded anywhere?
- No. Every measurement, quantity, and price you enter is calculated in your browser and never sent to a server, stored, or logged.
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