Linear Footage Calculator
Accurately calculate total length for fencing, trim, and construction projects.
How Do You Calculate Linear Ft?
Calculating linear feet (LF) is a fundamental skill for home improvement, carpentry, and construction. Unlike square feet (which measures area) or cubic feet (which measures volume), linear footage simply measures straight-line length.
The Basic Linear Footage Formula
To calculate linear feet for a single piece of material, use the following steps:
- Measure the length of the item in inches.
- Divide the total inches by 12.
- The result is the total linear feet.
Formula: Total Inches / 12 = Linear Feet
Example: Calculating Fencing or Trim
If you are buying baseboards for a room and you have measured three walls at 120 inches, 96 inches, and 120 inches:
- Total Inches: 120 + 96 + 120 = 336 inches.
- Calculation: 336 / 12 = 28.
- Result: You need 28 linear feet of trim.
Linear Feet vs. Square Feet
It is important not to confuse linear feet with square feet. Linear feet only cares about the length. For example, a 10-foot long 2×4 board and a 10-foot long 2×12 board are both exactly 10 linear feet, even though the 2×12 is much wider and covers more square footage.
When to Use Linear Footage
- Lumber: Framing studs, rafters, and pressure-treated boards.
- Trim & Molding: Baseboards, crown molding, and chair rails.
- Fencing: Calculating the total perimeter of a yard.
- Countertops: Often priced by the linear foot for standard depths.