About the Wood Weight Calculator
This wood weight calculator estimates how much a board, a stack of lumber or a log weighs. Choose the species, enter the actual dimensions and the moisture content, and it returns the weight per piece and in total (pounds and kilograms), the density at that moisture content, the volume and the board feet.
It is useful for planning a truck or trailer load, checking whether a beam can be lifted by hand, estimating shipping weight for furniture lumber, or working out what a green log will weigh before milling. Green wood can weigh twice as much as kiln-dried wood of the same size, so moisture content matters as much as species.
Densities follow the method in the USDA Forest Products Laboratory Wood Handbook: each species’ basic specific gravity is adjusted for shrinkage below the fiber saturation point (about 30% moisture) and the weight of the water is added. Kiln-dried framing lumber is typically around 12–19% moisture, air-dried lumber 12–20%, and freshly cut logs often 40–100% or more. Use actual sizes — a 2×4 is about 1.5 × 3.5 inches.
With the default inputs, the total weight is 9.9 lb. Change any value above to recalculate instantly.
How to use the wood weight calculator
- 1Pick the wood species (or enter a custom specific gravity).
- 2Enter the moisture content — about 12% for kiln-dried indoor lumber.
- 3Choose board or log and enter actual dimensions.
- 4Enter the number of pieces.
- 5Read the total weight in pounds and kilograms.
Formula and method
Specific gravity in the Wood Handbook is based on ovendry weight. Below the fiber saturation point (about 30% moisture) wood shrinks as it dries, so the specific gravity based on current volume, Gx, rises; the handbook’s Equation 4-13 estimates it from the basic specific gravity Gb (green volume) using a shrinkage of 26.5 × Gb percent. Above 30% the volume no longer changes and Gx equals Gb.
Density including water is then 62.4 lb/ft³ (water) × Gx × (1 + MC/100), Equation 4-14. Multiplying by the volume — thickness × width × length for lumber, πr² × length for a log — gives the weight. Real pieces vary by roughly ±10% around species averages.
- Gb
- Basic specific gravity (ovendry weight, green volume)
- MC
- Moisture content (% of ovendry weight)
- ρ
- Density including water (lb/ft³)
- V
- Volume (ft³)
Worked examples
One kiln-dried Douglas-fir 2×4, 8 ft
Gb 0.45 becomes Gx = 0.45 ÷ (1 − 0.265 × 0.45 × 0.6) = 0.485 at 12% moisture, so density is 62.4 × 0.485 × 1.12 = 33.9 lb/ft³. A 1.5 × 3.5 in × 8 ft stud is 0.292 ft³, about 9.9 lb.
Ten red oak 1×6 boards (3/4 × 5-1/2 in), 8 ft, at 8% moisture
Northern red oak (Gb 0.56) has Gx 0.628 at 8% moisture, a density of 42.3 lb/ft³. Each board is 0.229 ft³ (9.7 lb), so ten weigh about 97 lb.
Green loblolly pine log, 14 in × 10 ft at 60% moisture
Above 30% moisture specific gravity stays at the basic 0.47, so density is 62.4 × 0.47 × 1.6 = 46.9 lb/ft³. A 14 in × 10 ft cylinder holds 10.69 ft³, about 502 lb (228 kg).
Four white oak 4×4 posts (3.5 × 3.5 in), 8 ft
White oak (Gb 0.60) reaches 46.4 lb/ft³ at 12% moisture. Each 0.68 ft³ post weighs about 31.5 lb, so four weigh about 126 lb.
Frequently asked questions
How much does a 2×4 weigh?+
A kiln-dried 8 ft 2×4 (1.5 × 3.5 in) weighs roughly 8 to 10 lb depending on species: about 9.9 lb in Douglas-fir, 10.4 lb in loblolly southern pine and 7.1 lb in Engelmann spruce (SPF) at 12% moisture. A wet or green stud can weigh 30–60% more.
How much does green wood weigh compared to dry wood?+
Freshly cut wood often has 40–100%+ moisture content, so it can weigh 1.3 to 2 times as much as the same piece kiln-dried. Above about 30% moisture, all the extra weight is free water in the cells.
What is the heaviest common lumber?+
Among common North American woods, hickory, white oak and longleaf southern pine are among the heaviest, at roughly 41–50 lb per cubic foot at 12% moisture. Western redcedar, basswood and eastern white pine are among the lightest at about 23–25 lb.
What moisture content is kiln-dried lumber?+
Kiln-dried framing lumber is graded at 19% moisture or less (KD-19), and some is dried to 15% (KD-15). Furniture and flooring hardwoods are usually dried to about 6–9% to suit heated indoor conditions.
How do I find the moisture content of wood?+
Use a pin or pinless moisture meter, or weigh a sample, oven-dry it at about 103 °C (217 °F) until its weight stops changing, and divide the water lost by the dry weight.