Linear Feet Calculator

A linear feet calculator turns an area into a length of material. Divide the area in square feet by the width of one piece in feet. For 200 sq ft covered with 6 inch wide boards, the width is 0.5 ft, so 200 ÷ 0.5 = 400 linear feet.

The formula in plain words

Imagine laying boards edge to edge until the area is covered. Each board is one piece wide, and the total length of all the boards laid end to end is the linear footage.

If each board is half a foot wide, every linear foot covers half a square foot. To cover 200 sq ft you need twice as many linear feet as square feet, which is 400. If the boards were a full foot wide, linear feet and square feet would be equal.

The width is entered in inches because that is how boards are labeled. The calculator divides by 12 for you.

Worked examples

Example 1, the default: 200 sq ft with 6 inch material.

• Width in feet: 6 ÷ 12 = 0.5
• Linear feet: 200 ÷ 0.5 = 400 ft

Example 2, the real width of a “1x6” board. A nominal 1x6 measures about 5.5 inches wide, and a deck board labeled 6 inches may be 5.5 as well.

• Width in feet: 5.5 ÷ 12 = 0.4583
• Linear feet: 200 ÷ 0.4583 = 436.36 ft
• Using 6 inches instead would have left you 36 ft short

For flooring and shiplap, use the width that shows when the pieces are installed, not the width of the whole board. The tongue overlaps the next piece and does not count.

Linear feet for 200 sq ft

Material width	Linear feet needed
3.5 in	685.71 ft
5.5 in	436.36 ft
6 in	400.00 ft
7.25 in	248.28 ft
12 in	200.00 ft

How to measure

Measure the length and width of the surface and multiply to get square feet. For a room with a closet or alcove, add each rectangle. Subtract only large openings, like a built-in cabinet that the material will not cover.

Then check the product label for the face width of the piece. This is the number that goes in the width field. Convert metric widths to inches by dividing millimeters by 25.4.

Common mistakes

• Entering the nominal width. A 1x6 is 5.5 inches, not 6.
• Forgetting waste. The result is the net run, so order at least 10% more for end cuts.
• Mixing up linear feet and board feet. Linear feet count length only. Board feet include thickness, and the board foot calculator handles that.
• Ordering lengths that do not suit the room. A 12 ft room with 8 ft boards leaves a 4 ft offcut on each row. Pick lengths that fit the layout.
• Using the room area when material will only run along part of it.

From linear feet to a board count

Boards come in set lengths, so convert the run into pieces. Take the 436.36 ft needed for 200 sq ft of 5.5 inch boards.

• Add 10% for cuts: 436.36 × 1.10 = 480 ft
• Divide by the board length: 480 ÷ 8 ft = 60 boards
• If the boards were priced at $1.50 per linear foot, the material would be 480 × $1.50 = $720

The price is only an example. Use the lumber yard’s figure. A 12 ft or 16 ft board can mean fewer end joints and less waste on a long room, so check what is available.

Worked check with fence pickets

Pickets are another case. A fence section 8 ft long and 6 ft tall faces 48 sq ft. If the pickets are 5.5 inches wide with no gaps, you need 48 ÷ (5.5 ÷ 12) = 104.7 ft of picket, which is 17.4 pickets at 6 ft each, so 18. Gaps between pickets lower the coverage, so use the width plus the gap as the repeat width.

Related calculators

Get your area first with the square footage calculator, then convert it here. For flooring jobs, the flooring calculator counts boxes and the board foot calculator covers lumber priced by volume. Edge trim along the walls is a perimeter question, and the baseboard calculator handles it.