← Home & Construction Calculators
Calculate linear feet for lumber, trim, fencing, flooring, siding, pipe, cable and other continuous materials. Convert measurements, add waste, estimate stock pieces and calculate project cost.
Linear-foot symbols
Linear feet formulas
The tool converts every entered length to feet before calculating. It keeps the exact adjusted requirement separate from the whole-piece purchase quantity.
Visual measurement guide
Measure along the material path, including corners and returns. For trim, add each wall run. For flooring or siding, area mode estimates the combined length of all rows based on the installed face width.
Worked examples
Three trim sections
Three walls are each 40 ft long. Net length is 120 LF. With 10% waste, the requirement becomes 132 LF. Using 8-ft pieces:
Purchased length = 136 LF
Expected offcut = 4 LF
Area to linear feet
A 240 ft² surface covered with 6-inch-wide material requires:
240 ÷ 0.5 = 480 linear feet
Useful linear conversions
| Measurement | Linear feet |
|---|---|
| 1 inch | 0.083333 ft |
| 1 yard | 3 ft |
| 1 meter | 3.28084 ft |
| 1 centimeter | 0.0328084 ft |
| 12 feet | 4 yards |
Linear feet are different from square feet and board feet. Square feet measure surface area; board feet measure lumber volume; linear feet measure length.
Planning guidance by material
- Baseboard and crown molding: measure every wall and exclude only openings without trim.
- Fencing: include gates, corners and end sections, then calculate posts separately.
- Decking: area conversion uses installed board face width, not nominal width.
- Pipe and cable: include vertical rises, bends, service loops and routing changes.
- Siding: account for overlap because exposed coverage can be less than physical width.
Measurement checklist
- Sketch and label every run.
- Measure actual installed paths.
- Confirm stock lengths available locally.
- Add cutting waste before rounding pieces.
- Check whether price is per piece or per linear foot.
Frequently asked questions
What is a linear foot?
A linear foot is a one-dimensional measurement equal to 12 inches, regardless of material width or thickness.
How do I convert square feet to linear feet?
Divide the square-foot area by the material width expressed in feet.
How many linear feet are in an 8-foot board?
One 8-foot board provides 8 linear feet before cutting waste.
Should I round linear feet?
Keep the calculated length precise, but round the stock-piece count upward because partial pieces are normally not sold.
How much waste should I add?
Simple straight runs may need 5–10%; projects with angles, pattern matching or defects may need more.
Common mistakes
- Confusing linear feet with square or board feet.
- Using nominal width instead of installed coverage width.
- Forgetting corners, returns and vertical runs.
- Rounding before adding waste.
- Ignoring the stock lengths the supplier actually sells.