What Are Linear Feet?
Linear feet measure length only—it's a straight-line measurement ignoring width and thickness. Unlike board feet (which measure volume), linear feet simply tell you how long something is.
Linear Feet Formula
Linear Feet = Length (in feet)
That's it! No width or thickness calculations needed.
Important Note:
If your measurement is in inches, divide by 12 to convert to feet. If measuring in centimeters, divide by 30.48.
Practical Examples
Example 1: Baseboard Trim
Room perimeter: 48 feet
Linear feet needed = 48 feet
Width and thickness don't matter for pricing trim by linear foot
Example 2: Fence Rails
3 rails × 100 feet long each
Total linear feet = 3 × 100 = 300 feet
Each rail counts separately
Example 3: Multiple Pieces
Linear Feet vs Board Feet: Key Differences
| Aspect | Linear Feet | Board Feet |
|---|---|---|
| Measures | Length only | Volume (L × W × T) |
| Used for | Trim, molding, pipes, wire | Lumber, hardwood planks |
| Formula | Length in feet | (T × W × L) ÷ 12 |
| Example | 8-foot 2×4 = 8 linear feet | 8-foot 2×4 = 5.33 board feet |
When to Use Linear Feet Measurements
Common Linear Feet Applications:
- • Baseboard and crown molding
- • Electrical wire and conduit
- • Plumbing pipes
- • Chain link fencing
- • Rope and cable
- • Edge banding
- • Weatherstripping
Why Linear Feet Matter:
- • Simpler pricing for materials sold by length
- • Easy to measure with a tape measure
- • Standard for trim and molding quotes
- • Essential for perimeter calculations
- • Used in most installation estimates
Common Linear Feet Calculation Mistakes
❌ Confusing Linear and Board Feet
Don't multiply by width or thickness when calculating linear feet. A 2×4×8 is 8 linear feet, not 64 (2×4×8).
❌ Forgetting Unit Conversion
If measuring in inches, always divide by 12. A 96-inch board = 8 linear feet, not 96.
❌ Not Accounting for Waste
Add 10-15% extra for cuts, mistakes, and waste. If you need 100 linear feet, buy 110-115 feet.
Pro Tips for Linear Feet Calculations
Measuring Tips:
- • Use a quality tape measure
- • Measure twice, cut once
- • Round up to nearest foot for ordering
- • Mark measurements clearly
Ordering Tips:
- • Buy in standard lengths when possible
- • Consider delivery minimums
- • Account for inside/outside corners
- • Keep waste percentage in mind
Key Takeaways
- • Linear feet = length only (no width or thickness)
- • Convert inches to feet by dividing by 12
- • Add 10-15% waste to your total
- • Use for trim, molding, and materials sold by length
- • Different from board feet which measures volume