About
About boardfootmath.com
A free, independent set of lumber measurement tools — built to answer one question quickly: how much material do you need?
What this site is
boardfootmath.com is a small, independent collection of lumber measurement tools. It started with one board foot calculator and a linear feet calculator, both built around the same question: how much material do I actually need to buy?
The calculators run entirely in your browser. There are no accounts, no sign-up, and no upload of the measurements you type in. Every result is calculated on your device, so the numbers never depend on a request to our server.
Why we built it
Most lumber math is simple, but it is easy to get wrong at the lumber yard. Board feet, linear feet, and square feet measure three different things, and mixing them up is how people over-order by 20% or come up short on trim.
We wanted a page that does the arithmetic quickly, shows the formula, and explains the difference between the units in plain language. No paywall, no forced email signup, and no ten-step wizard before you see a number.
How the calculators work
Every calculator on this site uses the standard trade formulas. Board feet use length in feet, width and thickness in inches, divided by 12. Linear feet add up length only. Square footage multiplies length by width.
Hardwood thickness follows the quarters convention, so 4/4 is treated as 1 inch, 5/4 as 1.25 inches, and so on. Softwood is calculated on nominal dimensions unless you enter the actual dressed size yourself.
- Board feet = length (ft) × width (in) × thickness (in) ÷ 12
- Linear feet = sum of all lengths, in feet
- Square feet = linear feet × width in feet
Accuracy and limits
The math is checked against worked examples and unit tests, and results are rounded to two decimals. That said, these tools are estimates. Lumber is sold in fixed lengths, suppliers round differently, and waste depends on your cut list.
Always confirm the final quantity with your supplier before placing an order, and check the dimensions of the material you are actually buying. The site cannot account for defects, grading, or the way a particular yard measures and prices stock.
The calculators are decision aids, not professional advice. For structural work, follow your engineer's or building department's requirements.
How the site is funded
The site is free to use. It may display advertising in the future to cover hosting costs, through third-party networks such as Google AdSense. If ads are enabled, those networks may use cookies to show relevant ads, and the privacy policy explains how to opt out of personalized advertising. No ads are served today.
We do not sell your data, and we do not ask for information that is not needed to run the page.
Corrections and feedback
If a formula looks wrong, a preset is off, or a page is confusing, tell us. Email hello@boardfootmath.com with the page and the numbers you used, and we will check it. Corrections to the math are treated as the highest priority.