A board foot calculator turns lumber dimensions into a volume that can be used for quantities and pricing. Enter the thickness, width, length, and number of identical pieces to see the board feet for one piece and the total for the full order.
Unit Converter includes this workflow in its Construction Calculator, along with an estimated lumber cost from a price per thousand board feet. If you want a board foot calculator app for Android, iPhone, or iPad, Unit Converter is free to download.
What does one board foot measure?
A board foot is a unit of lumber volume. One board foot represents a piece that is 1 in thick, 12 in wide, and 1 ft long. The shape can change while the volume stays the same, which is why thickness, width, and length all matter.
When thickness and width are measured in inches and length is measured in feet, the board feet formula is:
Board feet = thickness × width × length ÷ 12
For one piece entered as 2 in thick, 6 in wide, and 8 ft long:
2 × 6 × 8 ÷ 12 = 8 board feet
The same calculation can then be multiplied by the number of identical pieces in the order.
Board feet calculator example for 50 pieces
Suppose the order contains 50 pieces, each entered as 2 in × 6 in × 8 ft. Each piece contains 8 board feet, so the complete quantity contains:
8 board feet × 50 pieces = 400 board feet
The quantity changes the total but not the individual result. Construction Calculator therefore provides both 400 total board feet and 8 board feet each on separate result pages.
Use the Lumber tool in Unit Converter
- Open Construction Calculator, press Shift, then press Volume to select Lumber.
- Enter 2 in for Thickness.
- Enter 6 in for Width.
- Enter 8 ft for Length.
- Enter 50 for Quantity.
- Enter the example price of 750 in the $/MBM field.
The first result shows the total board feet. Press Next to review board feet per piece, estimated total cost, estimated cost per piece, and total cubic feet without entering the dimensions again.
Lumber cost calculator using price per MBM
MBM means 1,000 board feet. A price of $750 per MBM means the supplier rate used in the example is $750 for each 1,000 board feet. The estimated order cost is calculated as:
Estimated cost = total board feet ÷ 1,000 × price per MBM
For 400 board feet at $750 per MBM:
400 ÷ 1,000 × $750 = $300
The same rate gives an estimated cost of $6 per piece because each piece contains 8 board feet. This makes the Lumber mode useful as both a volume calculator and a lumber cost calculator for a group of identical boards.
Watch the board-foot and lumber-cost calculation
See how the dimensions, quantity, and example price per MBM produce the total board feet, board feet per piece, estimated total cost, and estimated cost per piece.
Review every Lumber result
The five result pages answer different questions about the same order:
- Total Board Feet: 400 bf for all 50 pieces.
- Board Feet Each: 8 bf for one 2 in × 6 in × 8 ft piece.
- Total Cost: An estimated $300 at the example $750/MBM rate.
- Cost Per Piece: An estimated $6 for each piece at that rate.
- Cubic Feet: 33.333 cu ft for the complete lumber quantity.
One board foot equals one-twelfth of a cubic foot, so the volume check is 400 ÷ 12 = 33.333 cubic feet.
Price per board foot calculator in Helpful Tools
Unit Converter also includes a focused Board Foot Calculator in Helpful Tools. It accepts thickness, width, length, number of pieces, and a price per board foot, then returns total board feet and cost.
This price per board foot calculator is convenient when a quote is already expressed per board foot. Use Construction Calculator’s richer Lumber mode when the quote is expressed per MBM and you also want board feet per piece, cost per piece, and total cubic feet.
Match the calculation to the lumber quote
Use the dimensions and pricing basis shown by the supplier. Lumber can be quoted using nominal dimensions, measured dimensions, rough sizes, or surfaced sizes, so entering the same basis used by the quote keeps the estimate meaningful.
Set Quantity to the number of identical pieces planned for the order, including any additional pieces you have chosen for the project. Then enter the current supplier rate rather than relying on the $750/MBM training example.
Who can use a lumber board foot calculator?
Woodworkers, carpenters, cabinetmakers, furniture makers, lumber buyers, millwork estimators, and shop supervisors can use board-foot calculations to compare board sizes, total identical pieces, and turn an MBM quote into a quick material-cost estimate.
Because Lumber is part of Unit Converter’s Construction Calculator, the same app also includes feet-and-inches arithmetic and focused tools for stairs, balusters, studs, roofs, rafters, miters, areas, volumes, weights, and common shapes.
What makes a useful mobile board feet calculator?
- One-piece and order totals: See board feet for each board and the full quantity.
- Built-in MBM pricing: Apply a supplier rate per thousand board feet.
- Total and per-piece estimates: Review the complete order cost and the cost of one piece.
- Cubic-foot result: See the same total lumber volume in cubic feet.
- Simple result pages: Move through related answers with Next while keeping the original inputs.
- Related construction tools: Continue into dimensional math and other project calculations in the same app.
Frequently asked questions
Is there a free board foot calculator app?
Yes. Unit Converter is free to download from Google Play and the App Store. It includes the Lumber mode in Construction Calculator and a separate Board Foot Calculator in Helpful Tools.
How many board feet are in a 2 × 6 × 8 ft board?
Using the dimensions entered in this example, 2 × 6 × 8 ÷ 12 equals 8 board feet per piece.
What does $750 per MBM mean?
It means $750 per 1,000 board feet. A 400-board-foot order at that example rate has an estimated cost of $300.
Can I calculate board feet without adding a price?
Yes. The Lumber tool allows a zero price when only the board-foot and cubic-foot results are needed.
Does quantity change board feet per piece?
No. Quantity changes the total board feet and estimated total cost. The board feet for one piece remain based on its thickness, width, and length.
Is Board Foot Calculator a separate download?
No separate download is needed. Both board-foot workflows are included inside Unit Converter.
Calculate lumber volume and estimated cost
Enter one board’s dimensions, set the quantity, and apply the pricing format used by the quote. For help with fractional measurements, see our feet and inches calculator app guide. For the wider collection of building and estimating features, visit our Construction Calculator app guide.
Download Unit Converter on the App Store for iPhone or iPad, or get Unit Converter on Google Play for Android.