Fence Calculator

Planning your fence materials

Every fence is made of repeating sections between posts, so the quantities follow directly from the total length and the post spacing. The number of sections is the length divided by the spacing, rounded up. The number of posts is one more than the sections, because both ends need a post. A 100 ft fence with 8 ft spacing needs 13 sections and 14 posts, plus an extra post for every gate you add. The calculator handles this for you and treats each gate as a replacement for one fence section.

Pickets, boards and panels

For a built-in-place fence, set the picket width and the gap between pickets. The tool divides the section length by picket width plus gap to get the number of pickets per section, then multiplies by the number of fence sections. For privacy fences enter a gap of zero. Rails run horizontally between posts and are usually 2 or 3 per section depending on height. If you buy prefab panels instead, choose panels, set the spacing to the panel width, and the calculator returns the number of panels to purchase.

Waste and ordering tips

Add a waste allowance of 5 to 10 percent for damaged boards, miscuts and uneven ground. Concrete or gravel for post holes is not included, so allow roughly one to two bags of fast-setting concrete per post. Remember that posts should be buried about one third of their length, so a 6 ft tall fence needs 8 ft posts. Check local rules about maximum height, property line setbacks and required permits before you buy. Your numbers are processed locally in your browser and nothing is uploaded.

Example: a 100 ft privacy fence with 8 ft spacing, 5.5 in pickets, no gaps and one gate needs 13 sections, 15 posts including the one for the gate, 12 fenced sections and about 18 pickets per section. Measure along the actual fence line, including corners, and mark every post position before ordering.