Linear feet calculator
Linear feet calculator: square feet to linear feet and back.
Convert square feet to linear feet by board or plank width, convert linear feet back to square feet, or add up pieces — then get the stock pieces to buy with waste. 200 sq ft of 5.5 in boards is 436.4 linear feet.
200 sq ft at 5.5 in wide
436.4 lin ft
60 eight-foot pieces with 10% waste
100 lin ft at 5.5 in wide
45.8 sq ft
linear ft x width / 12
Key fact
Width decides it
equal only at 12 in wide
Next step
Turn linear feet into a material list
Linear feet is how boards, trim, and fencing are priced. Each project adds its own layout rules — pick the calculator for what you are building.
Formula shown
Linear feet, square feet, and width
Square feet to linear feet
linear ft = square ft x 12 / width (in)
Linear feet to square feet
square ft = linear ft x width (in) / 12
Stock pieces
pieces = ceil(linear ft x (1 + waste) / stock length)
Linear feet per square foot by width
| Material width | Lin ft per sq ft | Sq ft per 100 lin ft |
|---|---|---|
| 1x4 board (3.5 in) | 3.43 | 29.2 |
| 1x6 or 5/4x6 deck board (5.5 in) | 2.18 | 45.8 |
| 1x8 board (7.25 in) | 1.66 | 60.4 |
| 2.25 in hardwood strip | 5.33 | 18.8 |
| 5 in plank flooring | 2.4 | 41.7 |
| 12 in shelf or tile row | 1 | 100 |
Nominal size is not the real width
Lumber is sold by nominal size, but a 1x6 is 5.5 in wide and a 1x4 is 3.5 in. Using the nominal 6 in instead of 5.5 in under-orders by about 8%. Measure the face that will show, and for tongue-and-groove flooring use the exposed face, not the overall width.
Sources
- NIST unit conversions — length and area unit relationships (1 ft = 12 in, 1 sq ft = 144 sq in)
Sources checked
Checked against
Formulas and unit conversions checked against the sources listed on this page.
How we check our numbersLast updated: October 4, 2026
FAQ
Linear feet calculator questions
Answers for calculating linear feet, converting square feet to linear feet and back, and how width changes the result.
How do you calculate linear feet? + -
Linear feet is simply length measured in feet. Measure each piece in feet and add the lengths together: twelve 8 ft boards are 12 x 8 = 96 linear feet. Width and thickness do not change the linear footage.
How do I convert square feet to linear feet? + -
Divide the square footage by the width of the material in feet. For boards measured in inches, linear feet = square feet x 12 / width in inches. Covering 200 sq ft with 5.5 in wide boards takes 200 x 12 / 5.5 = 436.4 linear feet before waste.
How do I convert linear feet to square feet? + -
Multiply the linear feet by the width in feet: square feet = linear feet x width in inches / 12. For example, 100 linear feet of 5.5 in wide board covers 100 x 5.5 / 12 = 45.8 square feet.
Is a linear foot the same as a square foot? + -
No. A linear foot is a length of 12 inches; a square foot is an area of 12 by 12 inches. They are only equal for material that is exactly 12 inches wide. Narrower material needs more linear feet to cover one square foot, and wider material needs fewer.
How many linear feet are in a square foot of 1x6 boards? + -
A 1x6 board has an actual face width of 5.5 inches, so it takes 12 / 5.5 = 2.18 linear feet to cover one square foot. Always use the actual width, not the nominal size, and account for any gap between boards.
How much waste should I add? + -
A 10% allowance covers typical end cuts and a few defective pieces on straight layouts. Diagonal layouts, short rooms with many cuts, and lower lumber grades can need 15% or more. The waste field is editable.