Linear Foot Lumber Calculator
Convert between linear feet and board feet for any board size, and get the total cost — so you can compare lumber priced per foot or per board foot.
Quick Answer
Linear feet measure length only; board feet measure volume. Convert with LF = board feet x 12 / (thickness x width), or BF = thickness x width x linear feet / 12. A 1×6 board has 2 linear feet per board foot; a 2×4 has 1.5.
Linear Foot & Board Foot Calculator
Enter the board thickness and width, choose what you know (linear or board feet), and add a price. The calculator converts both ways and totals the cost.
How to Use This Calculator
Linear Foot Formula
Board feet = thickness x width x linear feet / 12
Linear feet = board feet x 12 / (thickness x width)
(thickness and width in inches)
Linear Feet per Board Foot
| Board (nominal) | Linear feet per board foot |
|---|---|
| 1×4 | 3.0 |
| 1×6 | 2.0 |
| 1×8 | 1.5 |
| 2×4 | 1.5 |
| 2×6 | 1.0 |
Common Mistakes to Avoid
- Mixing nominal (2×4) and actual (1.5 x 3.5) sizes in the conversion.
- Comparing a per-linear-foot price to a per-board-foot price without converting.
- Forgetting waste and offcuts when buying by linear feet.
- Assuming all 1×6 boards are exactly 6 inches wide.
When the Estimate May Be Wrong
Results depend on whether you use nominal or actual dimensions, and prices vary by species, grade, length, and region. Rough lumber is often sold by board foot and dimensional/trim by linear foot — always confirm the unit and size your supplier uses before ordering.
Linear Foot Lumber FAQs
How do you convert board feet to linear feet?
Use LF = board feet x 12 / (thickness x width), with thickness and width in inches. For example, 100 board feet of 2×4 lumber is 100 x 12 / (2 x 4) = 150 linear feet. Wider or thicker boards give fewer linear feet from the same volume.
What is a linear foot of lumber?
A linear foot measures length only — one foot along the board, regardless of its width or thickness. It is used for trim, moulding, and boards sold by length. A board foot, by contrast, measures volume (12 x 12 x 1 inch).
How many linear feet are in a board foot?
It depends on the board size. Linear feet = 12 / (thickness x width). A 1×6 board has 2 linear feet per board foot; a 2×4 has 1.5 linear feet per board foot. Thinner, narrower stock gives more linear feet per board foot.
Should I price lumber by linear foot or board foot?
Dimensional lumber, trim, and moulding are usually priced per linear foot; rough and hardwood lumber is usually priced per board foot. Convert to the same unit before comparing suppliers so you are not caught out on price.
Do I use nominal or actual size to convert?
Ask your supplier. A 2×4 is nominally 2 x 4 inches but actually 1.5 x 3.5 inches after milling. Using nominal size overstates volume; use the size your supplier prices on so board-foot and cost figures match the invoice.
Sources and Methodology
This is an original Woodworking Advisor calculator guide using standard lumber-measurement conversions with clear limitations.
- Board foot = thickness x width x length / 12 (inches and feet); linear feet convert as BF x 12 / (t x w).
- Nominal vs actual sizing affects results; use the dimensions your supplier prices on.
- Prices are user-entered; species, grade, length, and region all change real lumber pricing.
