Board feet in a 2×3×8
There are two honest answers. The wood you actually carry out of the store is 2.50 board feet — a 2×3 really measures 1.5″ × 2.5″. But if you're pricing or trading lumber, the industry counts this board as 4.00 BF, because board feet are by convention figured on the nominal 2″ × 3″ name.
The math, both ways
trade (nominal): 2″ × 3″ × 96″ ÷ 144 = 4.00 BF
Which one do you want? If you're figuring weight, volume, or "how much wood is that really," use 2.50. If you're comparing against hardwood priced per board foot, or reading a mill tally, use 4.00 — the whole trade runs on nominal, for the historical reasons on our nominal vs actual page. (Construction lumber itself is usually priced per piece, so at the store neither number appears on the shelf tag.)
What a 2×3 is for
The 2×3 is the wall stud's budget sibling — sold precisely because a closet partition or a basement chase wall doesn't need a 2×4's strength, and the half-inch saved per stud adds up across a room. Garage shelving frames and shop-fixture skeletons are its other natural habitat.
Know its limits: most codes accept 2×3 studs only for non-load-bearing partitions, and the skinnier section leaves less meat for wiring holes and drywall screws near edges. If a wall might ever hold cabinets, spend up for the 2×4 — future-you, drilling for a wire, will be grateful for the extra half inch.
Eight feet is the default length — it matches the ceiling, fits inside a pickup bed with the tailgate down, and wastes the least when cut for typical walls. It's usually the cheapest per foot, too, because it's the volume seller.
Heft check: at its true 1.5″ × 2.5″ section, a 8′ board holds 0.21 ft³ of wood — about 7.3 lb kiln-dried, and closer to 11 lb dripping fresh off the pressure-treated rack.
What that volume costs at hardwood prices
| Price per BF | Actual wood (2.50 BF) | Trade tally (4.00 BF) |
|---|---|---|
| $3.00 | $7.50 | $12.00 |
| $5.00 | $12.50 | $20.00 |
| $7.00 | $17.50 | $28.00 |
| $10.00 | $25.00 | $40.00 |
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