Add up piece lengths in feet, inches or meters, or convert an area in square feet into the linear feet of boards needed for a given board width. Add waste, choose the board length you buy and the price per linear foot to get the board count and total material cost.
Last updated:
Calculate from
Units: ft, in, m, cm, yd, or feet-inches like 7' 6". Lines without a unit use the default unit.
Actual face width: a nominal 1×6 is 5.5 in, a 2×4 is 3.5 in.
e.g. 0.125–0.25 in for decking; 0 for tongue and groove.
Buying
%
ft
$
Enter your values to see the result.
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How to use the Linear Feet Calculator
Choose a method: add up piece lengths, or cover an area with boards.
Enter the pieces (length and quantity per line) or the area plus the actual board width and any gap.
Add a waste allowance, usually 5–15% for cuts and defects.
Enter the board length you buy and the price per linear foot (both optional).
Press Calculate linear feet to see the total, boards needed and cost.
Linear feet formulas
From pieces:linear feet = Σ (length in feet × quantity). Inches ÷ 12, meters × 3.2808, centimeters × 0.0328.
From area:linear feet = square feet × 12 ÷ (board width in inches + gap).
Cost:total = linear feet × price per linear foot; when you buy whole boards, use boards × board length.
Example: a 12 × 20 ft deck (240 sq ft) with 5.5 in boards and 3/16 in gaps: 240 × 12 ÷ 5.6875 = 506.4 ft, plus 10% waste = 557 linear feet, or 35 boards of 16 ft.
Linear feet per 100 square feet
Nominal board
Actual width
Linear ft per 100 sq ft (no gap)
1×3
2.5 in
480
1×4 / 2×4
3.5 in
343
1×6 / 2×6 / 5/4×6
5.5 in
218
1×8 / 2×8
7.25 in
166
1×10 / 2×10
9.25 in
130
1×12 / 2×12
11.25 in
107
For tongue-and-groove boards and shiplap use the exposed face width (coverage width), which is smaller than the full board width.
Frequently asked questions
What is a linear foot?
A linear foot (also called a lineal foot) is simply 12 inches of length, measured along a board, pipe, trim or fabric regardless of its width or thickness. Lumber, molding and countertops are often priced per linear foot.
How do I convert square feet to linear feet?
Divide the area in square feet by the board width in feet, or multiply square feet by 12 and divide by the width in inches. Covering 240 sq ft with 5.5 inch wide boards needs 240 × 12 ÷ 5.5 = 523.6 linear feet before waste.
Should I use the nominal or the actual board width?
Use the actual width. A nominal 1×6 is really about 5.5 inches wide and a 2×6 decking board is about 5.5 inches, while 5/4×6 deck boards are usually 5.5 inches too. Using nominal sizes underestimates the boards you need.
How much waste should I add?
Around 5 to 10 percent is typical for straight runs and simple layouts, 10 to 15 percent for diagonal patterns, many cuts or lower-grade lumber that has defects.
What is the difference between linear feet and board feet?
Linear feet measure length only. Board feet measure volume: one board foot is 12 × 12 × 1 inch (144 cubic inches). Rough lumber and hardwoods are often sold by the board foot, trim and dimensional lumber by the linear foot or piece.
How do I calculate cost per linear foot?
Divide the price of a board by its length in feet. A 16 foot deck board that costs $41.60 costs $2.60 per linear foot. Multiply by the linear feet you need to get the total material cost.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.