Lumber Weight Calculator
What a board or a whole truckload weighs, from species, actual size and moisture content. Useful for loading a trailer, a roof or a shelf.
Total weight
10.5lb
- Each
- 10.5 lb
- In kilograms
- 4.8 kg
- Density used
- 36 lb/ft³
- Per board foot
- 3 lb
- Volume
- 0.29 ft³
Densities at 12% MC from the USDA Forest Products Laboratory Wood Handbook; individual boards vary ±10%.
Weight of common lumber (8 ft, kiln-dried 12%)
| Size | SPF | Douglas fir | Southern pine | Red oak |
|---|---|---|---|---|
| 2×4 | 7.9 lb | 9.6 lb | 10.5 lb | 12.8 lb |
| 2×6 | 12.4 lb | 15.1 lb | 16.5 lb | 20.2 lb |
| 2×8 | 16.3 lb | 19.9 lb | 21.8 lb | 26.6 lb |
| 2×10 | 20.8 lb | 25.4 lb | 27.8 lb | 33.9 lb |
| 2×12 | 25.3 lb | 30.9 lb | 33.8 lb | 41.3 lb |
| 4×4 | 18.4 lb | 22.5 lb | 24.5 lb | 29.9 lb |
| 6×6 | 45.4 lb | 55.5 lb | 60.5 lb | 73.9 lb |
Ask the shop
Stuck on a detail? Ask a question about this job. Your current inputs and results are sent along so the answer fits your numbers. AI answers can be wrong, so double-check anything structural with your building department.
Questions people ask
How much does a 2×4 weigh?
A kiln-dried 8 ft 2×4 (actual 1½" × 3½") in spruce-pine-fir weighs about 7–8 lb; in Douglas fir or southern yellow pine about 9–10 lb. A pressure-treated 2×4×8 that is still wet from treatment can weigh 12–15 lb.
How do you calculate the weight of lumber?
Weight = volume × density. Use the actual (surfaced) size: a 2×6 is 1½" × 5½". Volume in cubic feet = thickness × width × length (all in inches) ÷ 1,728. Multiply by the species density at your moisture content, e.g. 36 lb/ft³ for southern pine at 12%.
Why does pressure-treated lumber weigh so much more?
Treatment forces a water-based preservative into the wood, and most PT lumber is sold "wet" at 30–60% moisture content. It gets noticeably lighter as it dries. Boards stamped KDAT (kiln-dried after treatment) weigh about the same as untreated.
How much does a board foot of oak weigh?
Red oak at 12% moisture weighs about 44 lb/ft³, so one board foot (1/12 ft³) is about 3.7 lb. White oak is about 3.9 lb per board foot, walnut and soft maple about 3.2 lb, and eastern white pine about 2.1 lb.