Linear Foot Calculator
Convert square footage to linear feet based on material width
Frequently Asked Questions
How to calculate linear feet: quick answer
A linear foot is 12 inches of length. To get linear feet, add up the lengths of all pieces in inches and divide by 12, or add the lengths in feet directly. To find how many linear feet of boards cover an area, divide the square feet by the board width in feet (width in inches ÷ 12). To go the other way, multiply linear feet by the width in feet. The calculator above does all three and adds waste and cost.
Example: measuring trim or fence
You need 4 pieces of baseboard, each 8 ft 6 in long. 8 ft 6 in is 8.5 ft, so the total is 4 x 8.5 = 34 linear feet. With 10% waste for miter cuts, buy 37.4 linear feet; at $1.80 per linear foot that is about $67.
How to convert square feet to linear feet
Boards, trim and planks are sold by the linear foot, meaning length regardless of width. To find how many linear feet cover an area, divide the area by the width of the material in feet:
Linear feet = square feet ÷ (width in inches ÷ 12), then add a waste allowance.
Example
Covering 200 square feet with boards that cover 6 inches each takes 200 ÷ 0.5 = 400 linear feet. With 10% waste for cuts and defects you need 440 linear feet. At $2.50 per linear foot the material costs $1,100.
Linear feet per 100 sq ft by board width
| Coverage width | Linear feet (no waste) |
|---|---|
| 3.5 in | 343 |
| 5.5 in | 218 |
| 7.25 in | 166 |
| 9.25 in | 130 |
| 11.25 in | 107 |
Linear feet to square feet
| Linear feet | 3.5 in wide | 5.5 in wide | 7.25 in wide | 12 in wide |
|---|---|---|---|---|
| 10 | 2.9 sq ft | 4.6 sq ft | 6.0 sq ft | 10 sq ft |
| 50 | 14.6 sq ft | 22.9 sq ft | 30.2 sq ft | 50 sq ft |
| 100 | 29.2 sq ft | 45.8 sq ft | 60.4 sq ft | 100 sq ft |
| 500 | 145.8 sq ft | 229.2 sq ft | 302.1 sq ft | 500 sq ft |
Common jobs priced per linear foot (2026 ballpark)
| Item | Typical material or installed price |
|---|---|
| Baseboard and trim | $1 to $4 material, $4 to $10 installed |
| Wood privacy fence | $20 to $45 installed |
| Gutters (aluminum) | $6 to $15 installed |
| Countertops (laminate to quartz) | about $25 to $200+ per linear foot of run |
| Kitchen cabinets | about $150 to $600+ per linear foot |
Prices vary widely by region and material; use quotes from local suppliers in the price field for an accurate total.
Use the real coverage width
- Nominal vs actual: lumber sizes are nominal. A 1×6 board is actually 5.5 inches wide and a 1×8 is 7.25 inches.
- Overlaps and joints: tongue-and-groove boards and lap siding cover less than their full width. Measure the exposed face, often about half an inch less.
- Gaps: deck boards are usually spaced about 1/8 to 1/4 inch apart, which slightly increases coverage per board.
Choosing a waste factor
Use about 5% to 10% for straight runs in simple rooms, 10% to 15% for diagonal layouts or many corners, and more if the material has knots or defects you will cut out. Buying board lengths that match your runs also reduces waste.
Linear feet vs board feet
Linear feet ignore thickness and width. Hardwood lumber is often sold by the board foot instead, a volume unit equal to 144 cubic inches (12 × 12 × 1 inch).
For a full framing and decking list, use the lumber calculator or the deck material calculator. For flooring sold by the square foot, try the flooring calculator, for fences the fence material calculator, and for trim and siding the siding calculator.