How many board feet are in a 2x4?
An 8-foot 2x4 is 5.33 board feet, counted the way a yard counts it — on the nominal size, not the dressed one. Here is every common length, and why the two numbers differ.
An 8' 2x4 is 5.33 board feet.
Two-thirds of a board foot per foot of length: 0.667 bf/ft, so the length in feet × 0.667 gives it for any 2x4.
How that is worked out
- A board foot is 144 cubic inches — nominally a piece 12" × 12" × 1". Length × width × thickness in inches, divided by 144.
- For a 2x4, softwood is counted on the nominal size: 96" × 4" × 2" ÷ 144 = 5.33 bf.
- Counted on the dressed 1 1/2" × 3 1/2" it would be 3.50 bf — 34% less. The yard charges the first number.
Board feet per piece, counted on the nominal size
| Length | 2x4 | 2x6 | 2x8 | 2x10 | 2x12 |
|---|---|---|---|---|---|
| 8' | 5.33 | 8.00 | 10.67 | 13.33 | 16.00 |
| 10' | 6.67 | 10.00 | 13.33 | 16.67 | 20.00 |
| 12' | 8.00 | 12.00 | 16.00 | 20.00 | 24.00 |
| 14' | 9.33 | 14.00 | 18.67 | 23.33 | 28.00 |
| 16' | 10.67 | 16.00 | 21.33 | 26.67 | 32.00 |
Worth knowing
- Softwood by the stick is usually priced per piece, not per board foot. The board foot figure matters when you are comparing a price per thousand board feet (MBF) against a price per piece, or costing a framing package.
- Hardwood is the opposite: it is sold by the board foot and measured rough, so the number you are charged for is the wood before it was dressed. That is what the board foot calculator works out.
- Nothing here allows for waste. A framing take-off wants 10–15% on top for cuts, crooked sticks and mistakes.
Work out your own numbers
- Board foot calculator
How much lumber to buy for a finished piece, what it will cost, and what to ask for at the yard.
- Wall framing stud count
Field studs at 16" or 24" on centre, corner studs, and the king and jack studs every opening adds.
Related questions
- How many board feet are in a 2x4x8?
- 5.33 board feet. 96" long × 4" × 2" ÷ 144 = 5.33. That uses the nominal 2x4 rather than the dressed 1 1/2" × 3 1/2", because softwood board footage is reckoned on the name — which is also how the yard invoices it.
- Should I use the nominal or the actual size to work out board feet?
- Nominal, for softwood sold as a 2x4 or a 2x6. Actual, for anything where you are paying for the wood in front of you — hardwood by the board foot is measured rough, and rough is close to actual. Using the dressed size on softwood undercounts by about a third, which is the difference between your estimate and the invoice.
- How many 2x4s are in a thousand board feet?
- About 188 eight-footers, at 5.33 bf each. MBF pricing is how lumber futures and mill quotes are written, so it is the unit to convert into when you are checking whether a per-piece price at the yard is reasonable.