Board Feet Calculator
Board feet in a piece of timber, the total for a batch, the volume in cubic metres, cost and rough weight.
Results
What this tool does
Hardwood is sold by volume, not by length, which is why a wide board costs more per foot than a narrow one of the same thickness. The weight uses 550 kg/m³, a fair average for dry softwood; oak is nearer 700 and balsa nearer 160, so change the figure in your head if it matters for carrying.
Formula
board feet = thickness(in) × width(in) × length(ft) ÷ 12
Variables
| Symbol | Meaning | Unit |
|---|---|---|
th | Thickness | in |
wd | Width | in |
lg | Length | ft |
np | Pieces | — |
pr | Price per unit | — |
BF | Board feet | bf |
TT | Board feet | bf |
M3 | Volume | m³ |
CO | Cost | — |
KG | Mass | kg |
Worked example
- Thickness2 in
- Width6 in
- Length8 ft
- Pieces10
- Price per unit4.5
- Board feet8.0000 bf
- Board feet80.000 bf
- Volume0.18878 m³
- Cost360.00
- Mass103.83 kg
Limitations
- Density changes with temperature, moisture and composition. Use a value from the supplier's data sheet whenever precision matters.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.
- US and imperial (UK) units with the same name are not the same size. Check which system your figures come from.
Frequently asked questions
Is a board foot the same as a foot of board?
No, and the confusion costs money. A board foot is a unit of volume: one foot square by one inch thick, or 144 cubic inches. A two by six eight feet long is eight board feet, not eight feet. Hardwood is also usually sold rough and measured before planing, so the finished piece is thinner than what you paid for.