For hauling, freight & drying
Board Foot Weight Calculator
You already have the board feet — from the cut list or the dealer's ticket. This page turns that number into pounds at the moisture the lumber is actually at, and back again when all you have is a scale weight.
How do you calculate the weight of board feet?
Weight = board feet × pounds per board foot. The only hard part is the second number, because it is not a constant — it moves with the species and with how wet the wood is. Kiln-dried hardwood at about 8% moisture content runs roughly 2 to 4.2 lb per board foot across the common species, which is why two identical-looking bundles of the same footage can be a hundred pounds apart.
This site's calculator works from the kiln-dried figure and adjusts it, so it needs two inputs you may not have seen asked before: the board feet (not the dimensions) and the moisture content.
| Species | lb per BF, kiln-dried (8%) | 100 BF at 8% | 100 BF at 30% (green) |
|---|---|---|---|
| Hickory | 4.2 | 420 lb | 505.6 lb |
| White oak | 4.0 | 400 lb | 481.5 lb |
| Hard maple | 3.9 | 390 lb | 469.4 lb |
| Red oak | 3.8 | 380 lb | 457.4 lb |
| Birch | 3.7 | 370 lb | 445.4 lb |
| Ash | 3.5 | 350 lb | 421.3 lb |
| Mahogany | 3.4 | 340 lb | 409.3 lb |
| Walnut / soft maple | 3.2 | 320 lb | 385.2 lb |
| Cherry | 3.0 | 300 lb | 361.1 lb |
| Douglas fir | 2.6 | 260 lb | 313.0 lb |
| Poplar | 2.5 | 250 lb | 300.9 lb |
| Pine | 2.1 | 210 lb | 252.8 lb |
| Cedar | 1.9 | 190 lb | 228.7 lb |
These are typical planning averages for the species as the trade counts them, not a mill certificate. Your own scale reading always beats the table, and where the number decides whether a trailer is legal, weigh it.
How much does moisture content change the weight?
A lot, and in one direction only. Wood in a kiln-dried stack still holds about 8% of its oven-dry mass as water, and the water leaves when the wood dries. Going the other way, green stock off the saw can sit at 30% moisture content or well above it. This calculator adds the water mass to the oven-dry weight, so the same 100 board feet reads about 20% heavier green than kiln-dried — a fixed ratio, not a per-species one.
Worked example, the one I run most often: 120 board feet of white oak.
- Kiln-dried at 8%: 120 × 4.0 = 480 lb (217.7 kg)
- At 30% moisture: 577.8 lb (262.1 kg)
- Difference: 97.8 lb, or 20.4% heavier — about the weight of a grown adult, on one small order
Scale that to a real purchase: a mixed 500 BF order of 300 BF red oak and 200 BF poplar weighs 1,640 lb kiln-dried and 1,974 lb green. Same boards, same board feet, 334 lb of water.
It treats water as pure added mass on top of the oven-dry weight, which is the standard approximation and is close enough to plan a trailer, a freight bill or a hoist. It does not model cell-wall saturation, which is why two species at the same stated moisture content can still differ a few percent on a real scale.
Can you work backwards from a weight to board feet?
Yes, and this is the direction nobody else's calculator seems to answer — it is also the one that comes up when a load has already been through the scale house. Divide the weighed total by the pounds per board foot at that moisture content:
Board feet = weight ÷ (oven-dry lb/BF × (1 + MC)).
Take 1,000 lb of white oak at 30% moisture. At 4.815 lb per board foot that is 207.69 board feet. Read the same 1,000 lb as if it were kiln-dried and you get 250 board feet — a 42.31 BF error, roughly 20%, purely from assuming the wood was dry. Same arithmetic on a 1,500 lb bundle of red oak at 20% MC: 355.26 board feet.
That is the trap when buying green hardwood by the approximate weight, and it is the flip side of the tally problem on the dealer's side — see gross vs net tally for the same gap expressed in board feet instead of pounds.
When does lumber weight actually matter?
Four moments, and none of them is the invoice:
- Loading your own vehicle. Take the payload figure from the truck's own door placard, not from a memory of what it carried last time, and divide it by the lb/BF number for the species at the moisture you are picking up. On a 1,200 lb payload allowance that is 300 BF of kiln-dried white oak, but only about 249 BF of the same oak green.
- Freight quotes. Carriers price by weight class, so a wet stack can move you into a higher rate on an order that costs the same in board feet.
- Shop handling. A hoist, jib or table rated for a load is rated in pounds, and a 500 BF bundle of hickory is not the same animal as 500 BF of poplar.
- Drying and stacking. Sticky-up stacks, rack capacity and floor loading all depend on the wet weight, which is the number you are trying to shed.
Solid lumber is bought and sold by the board foot. A scale reading tells you about moisture and freight, not about price — and it certainly does not tell you how many board feet the dealer thinks he sold you. For that, go from dimensions with the board foot formula and check the ticket.
Frequently asked questions
How many pounds is a board foot?
Roughly 2 to 4.2 pounds at kiln-dried (8%) moisture, depending on species: pine is about 2.1 lb per board foot, white oak 4.0, hickory 4.2. A board foot is 144 cubic inches of wood, so the weight is simply that volume at the species density.
How much heavier is green lumber than kiln-dried?
About 20% heavier on this calculator’s model, which adds the water mass to the oven-dry weight. A 30% moisture content on a 120 board foot white oak order turns 480 pounds kiln-dried into 577.8 pounds, a difference of 97.8 pounds.
Can I calculate board feet from a weight?
Yes, if you know the species and the moisture content. Divide the weighed total by the pounds per board foot at that moisture: 1,000 pounds of white oak at 30% moisture is 207.69 board feet, while the same 1,000 pounds kiln-dried is 250 board feet.
Do lumber yards sell wood by weight?
No. Solid lumber is sold by the board foot, and weight only matters for hauling, freight classification, hoisting and drying. A heavier stack is not a bigger order — it is usually a wetter one. The exception is firewood, which is sold by the cord, not the board foot.