Linear Feet Calculator
Calculate linear feet needed to cover an area from the area in square feet and the material's width, for flooring, siding, or fencing runs.
Linear feet is the total length of material you need to cover an area, when that material comes in fixed-width pieces like boards, planks, or pickets rather than being sold by the square foot.
How this calculator works
The calculator takes the total area you need to cover and the width of a single piece of material, and figures out how many feet of that material, laid edge to edge, would add up to the same coverage. Material width is usually given in inches, so it’s first converted to feet before dividing.
Formula: Linear feet = area in sq ft ÷ (material width in inches ÷ 12).
Worked example
200 sq ft to cover with boards that are 6 inches wide:
- Material width in feet: 6 ÷ 12 = 0.5 ft
- Linear feet: 200 ÷ 0.5 = 400 linear ft
Notes
This is the calculation behind ordering flooring boards, fence pickets, or siding by length. It converts an area you need to cover into a total run length of material.
Narrower material always needs more linear feet to cover the same area than wider material does, since each foot of a narrow piece covers less ground. A wider board or panel covers more area per linear foot, so fewer total feet are needed.
The result here is the raw linear footage with nothing added for waste. It’s common practice to add a waste allowance, typically around 10%, on top of the raw linear footage to account for cuts and trimming at the ends of a run.
How to use
Enter the total area you need to cover in square feet, and the width of the material you’re using in inches. The calculator returns the total linear feet needed, before any waste allowance. Add your own buffer for cuts before finalizing a material order.
A pure geometry calculation. Always double-check real-world measurements before ordering material.
Frequently asked questions
What's the formula for linear feet?
Linear feet = area in square feet ÷ (material width in inches ÷ 12). You first convert the material's width from inches to feet, then divide the total area you're covering by that width to find the total length of material needed.
Why does narrower material need more linear feet?
A narrower board or plank covers less area per foot of its length, so it takes more feet of it laid end to end to cover the same total area. A wider board covers more area per foot, so fewer linear feet are needed to reach the same square footage.
What projects use linear feet instead of square feet?
Ordering flooring boards, fence pickets, siding, baseboard, or trim — any material sold and installed as individual lengths rather than by the square foot. You know the area you need to cover and the material's width, and linear feet tells you how much total length to buy.
Should I add extra to the linear feet result before ordering?
Yes — this calculator gives the raw linear footage with no allowance for waste. Add extra for cuts, trimming at ends, and mistakes, typically around 10% on top of the calculated linear footage, before placing a material order.
Estimates only. Verify quantities with your supplier before purchasing.