Square Feet to Linear Feet Calculator
Convert an area in square feet into linear feet for boards, planks, or trim of a given width — handy for flooring, decking, and fencing.
What your result means
Linear feet needed is the running length of boards or planks to cover your area, given how wide each piece is, with a waste margin added. Before waste is the bare conversion. Flooring, decking, and trim are sold by length but cover an area, so this bridges the two. Start from area with our square footage calculator.
How to use this calculator
- Enter the area to cover in square feet.
- Enter the material's width in inches (a plank or board face width).
- Add a waste margin — 10% covers most cuts.
- Read the linear feet to buy.
- Round up to whole boards at the lengths your supplier stocks.
The formula
Dividing area by the piece width gives length, and multiplying area (sq ft) by 12 converts the width from inches so the units work out to linear feet. Add waste for cuts.
Worked example
Covering 200 square feet with 5-inch-wide flooring: 200 × 12 / 5 = 480 linear feet. Add a 10% waste margin and you'd buy about 528 linear feet to be safe.
Linear feet per 100 sq ft by width
| Material width | Linear feet / 100 sq ft |
|---|---|
| 3.25 in | 369 ln ft |
| 5 in | 240 ln ft |
| 6 in | 200 ln ft |
| 7.25 in | 166 ln ft |
| Add waste | +10% typical |
Tips & gotchas
- Use the board's actual face-cover width, not its nominal name.
- Add 10% for straight runs, 15%+ for diagonal or herringbone layouts.
- Buy in the stock lengths your supplier carries to cut down on waste.
- Decking spacing gaps slightly increase coverage — a small bonus, not a margin to rely on.
- Keep a few extra boards for future repairs and color matching.
Frequently asked questions
How do I convert square feet to linear feet?
Multiply the area by 12 and divide by the material width in inches. 200 sq ft of 5-inch material is 480 linear feet.
Why do I need the material width?
Square feet measures area; linear feet measures length. The width tells you how much area each foot of length covers, linking the two.
How much waste should I add?
About 10% for straight layouts and 15% or more for diagonal, herringbone, or cut-heavy patterns.
Does this work for decking and trim?
Yes. Any material sold by length but installed across an area — flooring, decking, fencing boards, trim — works the same way.
Should I use nominal or actual width?
Use the actual covering width. A board called 6 inches may only cover 5.5 inches, which changes the linear footage.
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