calculator for linear feet

What Is a Linear Foot?

A linear foot is simply a measurement of length equal to 12 inches. Unlike square feet, linear feet ignore width and thickness. If you buy a 10-foot board, you are buying 10 linear feet of material, no matter whether the board is 2 inches wide or 12 inches wide.

This is why linear feet are common for materials sold by length: lumber, trim, pipe, wire, chain, fence rails, fabric rolls, and baseboards.

Linear Feet Formula

Single item formula

Linear Feet = Quantity × Length per Piece

Multiple item formula

Total Linear Feet = Sum of all (Quantity × Length per Piece)

With waste allowance

Adjusted Linear Feet = Total Linear Feet × (1 + Waste% / 100)

Unit Conversions Used in This Calculator

• 1 foot = 12 inches
• 1 yard = 3 feet
• 1 meter = 3.28084 feet
• 1 centimeter = 0.0328084 feet

If your project list contains mixed units (for example, some measurements in inches and some in meters), this calculator combines them into one clear total in linear feet.

How to Use This Calculator for Linear Feet

1. Add one line item for each material size or segment.
2. Enter quantity and length.
3. Select the correct unit for each line.
4. Optionally add a waste percentage (recommended for cuts and mistakes).
5. Optionally enter your price per linear foot to estimate total cost.
6. Click Calculate Total.

Practical Examples

Example 1: Baseboard Trim

You need 14 pieces at 8 feet each.

• 14 × 8 = 112 linear feet
• Add 10% waste: 112 × 1.10 = 123.2 linear feet

Example 2: Fence Material

You have two runs:

• 6 sections at 12 feet
• 3 sections at 9 feet

Total = (6 × 12) + (3 × 9) = 72 + 27 = 99 linear feet

Example 3: Cable and Conduit

Suppose you measured:

• 150 feet of main run
• 240 inches of branch lines (20 feet)

Total = 150 + 20 = 170 linear feet

Common Mistakes to Avoid

• Confusing linear feet with square feet: linear feet measure length only; square feet measure area.
• Skipping waste: corners, miter cuts, and errors usually require extra material.
• Mixing units incorrectly: always convert inches, yards, or meters to feet before final totals.
• Forgetting overlaps: some installations require overlap, which increases total length needed.

Linear Feet vs. Square Feet vs. Board Feet

Linear feet

Length only. Used for trim, rope, conduit, and piping.

Square feet

Area (length × width). Used for flooring, paint coverage, roofing, and tile.

Board feet

Volume of lumber thickness and width. Used in sawmills and rough lumber pricing.

When Should You Add Waste?

For most jobs, adding waste is smart planning. Typical ranges:

• Simple straight runs: 5%
• Moderate cuts and corners: 8%–12%
• Complex layouts: 12%–15%+

If material is expensive, a careful estimate and a small overage can prevent costly second trips and mismatched batches.

Final Tip

Always measure twice and calculate once. Save your measurements in a list, then enter each line item into this calculator to get a clear, accurate linear foot total and optional budget estimate. This simple step can make your project faster, cleaner, and less expensive.