Construction & Materials
Lumber Calculator
Lumber: lumber Calculator totals board feet from each piece’s thickness, width and length and sums the order. Worked through below with real figures, and the calculator repeats the working on your own inputs — free, on-device, instant.
Enter your number of pieces, thickness, width and length and Lumber Calculator works out the total board feet for the order with each piece's thickness, width and length — fast, free and private, with no sign-up or uploads.
Estimate only — not engineering or contractor advice. Quantities depend on the dimensions and board sizes you enter, plus the gap, joist spacing and waste %; allow for usable lengths and offcuts.
About this calculator
It matters before you buy: a clean volume estimate plus a waste allowance beats a guess every time. The governing relationship: Lumber Calculator totals board feet from each piece’s thickness, width and length and sums the order. See it on real numbers: 24 studs at 2.4 m each = 57.6 linear metres of timber; board-foot or length pricing then gives the cost. The calculator above applies the same steps to whatever you enter — computed locally, nothing sent anywhere.
How to use
- Enter the number of pieces.
- Enter the board thickness in inches.
- Enter the board width in inches and the length in feet.
- Tap Calculate to see the total board feet.
Why use the Lumber Calculator
Instant
Every quantity is worked out on your device the moment you tap Calculate.
Private
The numbers you enter stay in your browser and are never uploaded or saved.
Free
No signup, no paywall, and no ads placed inside your results.
Works offline
Once the page has loaded it keeps working on a weak or dropped connection.
Mobile-first
Laid out for phones and tablets on site just as much as for desktops.
Planning estimates
Results are simplified planning estimates; real material needs vary by product size, waste, layout, local codes, and site conditions, so confirm before you buy or build.
Common uses
Use it when pricing timber by board foot
Use it for a framing or joinery order
Use it when allowing for usable lengths and offcuts
Use it when budgeting a timber purchase
Use it when totalling board feet
Use it for contractor and client quotes
Technical notes
Lumber Calculator totals board feet from each piece’s thickness, width and length and sums the order.
Totals board feet from the pieces you enter; round up for usable lengths and offcuts.
Nothing you type is uploaded — the calculation happens entirely on your device.
Worked example
24 studs at 2.4 m each = 57.6 linear metres of timber; board-foot or length pricing then gives the cost.
FAQ
How are board feet worked out?
Pieces times thickness times width in inches times length in feet, divided by 12, gives board feet.
Does the Lumber Calculator keep my entries private?
Yes. The Lumber Calculator runs in your browser, so nothing you enter is uploaded or saved.
Why divide by 12 and not 144?
When the length is already in feet, the board-foot formula divides by 12 rather than 144.
Should I use nominal or actual sizes?
Board feet use nominal sizes; dressed lumber is slightly smaller, so allow for that when fitting.