Free Lumber Calculator: Board Feet and Wall Studs
Two calculators in one. The first turns pieces of lumber into board feet, linear feet and a total cost, whichever way your yard prices it. The second counts studs, plates and headers for a framed wall, using the same rules as LaraKey’s takeoff calculator.
Board feet and cost
Wall framing
Estimates only. Measure on site and check with your supplier before you order.
How to calculate lumber
Board feet = Thickness (in) × Width (in) × Length (ft) ÷ 12, using nominal sizes
Linear feet = Length × Pieces
Studs = Wall length (in) ÷ Spacing + 1, plus 2 per corner, 2 per intersecting wall and 4 per opening (king and jack studs), plus waste
Plates = Wall length × 3 (bottom plate and double top plate) ÷ 16 ft + 5%
Headers = Openings × 2 plies × (Opening width + 3 in) ÷ 12 ft + 5%
Examples
Twenty 2 × 10s, 12 ft long
2 × 10 × 12 ÷ 12 = 20 board feet each, 400 board feet in all, 240 linear feet. At $18.98 a piece, $379.60, or $0.95 a board foot.
A 40 ft run of 8 ft wall
At 16 in on center: 31 studs, + 2 corners × 2 + 1 tee × 2 + 3 openings × 4 = 49, + 10% = 54 studs. Plates: 40 × 3 ÷ 16 + 5% = 8 plates.
Lumber Calculator: common questions
What is a board foot?
A volume of lumber 1 inch thick, 12 inches wide and 12 inches long, or 144 cubic inches. Hardwoods and some framing lumber are priced by the board foot.
Do I use nominal or actual sizes for board feet?
Nominal. A 2 × 4 is figured as 2 × 4, even though it’s really 1.5 × 3.5 inches.
How many studs do I need for a wall?
One every 16 inches (or 24) plus one to close the end, then extras for corners, intersections and the king and jack studs at each opening. Add about 10% for waste and crooked studs.
Why three plates?
A standard wall has one bottom plate and a double top plate. The second top plate ties walls together at corners.
How do I size headers?
Header size depends on the span and the load above. This calculator counts header stock; check your local code or an engineer for sizing.
What is linear feet?
Just the total length: 20 boards at 12 feet is 240 linear feet. Trim and some decking is priced this way.
Can I compare prices between yards?
Yes. Switch “Price is” between per piece, per board foot and per linear foot to compare quotes on the same order.
Are these numbers exact?
They’re estimates. Framing layouts vary; check your plans and local code.
Talk to a person who knows remodeling.
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