Key Takeaways
- Each picket takes up its width plus the gap to the next one
- Wider gaps mean fewer pickets per foot, even at the same picket width
- A 10 percent waste allowance covers end cuts and irregular spans
- Rail rows run the full fence length; most fences use 2 or 3 rows
Picket count depends on more than picket width alone. The gap between pickets, whether it is a tight privacy fence or a picket fence with visible spacing, changes how many pickets a given fence length actually needs.
Coverage per picket, not just width
Each picket occupies its own width plus the gap before the next picket starts. A 5.5 inch picket with a 0.25 inch gap effectively covers 5.75 inches of fence line. Dividing the total fence length, converted to inches, by that combined coverage gives the raw picket count before waste. A 100 foot fence (1,200 inches) at that coverage needs about 1,200 / 5.75 = 208.7 pickets before waste, rounding up with a waste allowance to 230.
This is the same width-plus-gap logic the deck board calculator uses for decking boards: the physical material is narrower than the space it effectively occupies once the gap is accounted for.
Waste allowance
End cuts, an odd final span that does not divide evenly, and the occasional damaged picket all add up. A 10 percent waste allowance is a reasonable default; a fence with corners or an irregular run may need more.
Picket count and post count are separate questions
Picket count is about the visible fence face; it does not tell you how many posts or how much concrete the frame underneath needs, that is a different calculation covered separately.
Rail footage
Rails run horizontally the full length of the fence, one line per row. Most residential fences use 2 rows for a shorter fence and 3 for taller privacy fencing. Multiplying fence length by the number of rows gives the total rail footage: 100 feet of fence at 2 rows needs 200 feet of rail.
Use the fence picket calculator to work out picket count and rail footage for your own fence dimensions. For post count and setting concrete, see the fence post calculator, and for a combined picket, post, rail and gate estimate on one page, the fence calculator covers the whole project.