Board feet and linear feet answer different questions. Board feet measure volume. Linear feet measure length along a board, trim piece, rail, or timber.
When Board Feet Help
Board feet are useful when thickness and width vary, especially with rough lumber, slabs, and stock sold by volume.
This makes it easier to compare boards that are not the same size.
When Linear Feet Help
Linear feet are useful when the profile and cross-section are already fixed, such as trim, decking, framing members, and moulding.
If every piece has the same size, length-based pricing can be easier to use.
Conversion Formula
To convert linear feet to board feet, you need thickness and width: board feet = thickness_inches x width_inches x length_feet / 12.
You cannot convert length alone into board feet because board feet measure volume, not just distance.
Worked Example
Ten linear feet of 2 inch by 6 inch rough stock is 10 board feet because 2 x 6 x 10 / 12 = 10.
Ten linear feet of 1 inch by 6 inch stock is only 5 board feet. The length is the same, but the volume is different.
Common Mistakes
A common error is comparing a board-foot price with a linear-foot price without converting both to the same basis.
Another mistake is using the nominal size name instead of the actual measured thickness and width.
FAQs
Can I convert linear feet to board feet?
Yes, but you need thickness and width. Length alone is not enough to calculate volume.
Which measurement should I use for a cut list?
Use the measurement that matches how the material is sold, then keep part dimensions in the cut list for layout.
Estimates only
These results are estimates only. Verify measurements, material specifications, structural requirements, safety requirements, and local building rules before buying materials or building.