Picket & board count calculator
Find how many pickets or fence boards you need for a run, from the picket width and the gap between them, plus a waste allowance.
Calculator
100 ft of 3.50" pickets at a 1.75" gap needs about 229 pickets — buy 252 with 10% waste. Picket widths 3.5"/5.5" and gaps 0–2.5" are labeled typicals — measure your product.
Pickets repeat on a fixed rhythm: each picket occupies its own width plus the gap to the next one. So the count for a run is simply the run length (in inches) divided by that repeat distance, rounded up. Set the gap to zero and the same formula counts butted privacy boards; open the gap to 1.75" and it counts a classic spaced picket.
Width matters as much as the gap. A 3.5" picket at a 1.75" gap repeats every 5.25", so 100 ft (1,200 in) takes about 229 pickets. Switch to wider 5.5" boards butted tight and the same run takes far fewer. Because real lumber is milled a little under nominal and ends split, always buy a waste allowance on top — 10% is a sensible default.
For overlapping styles the coverage math changes: board-on-board and shadowbox overlap each board, so effective coverage is the board width minus the overlap. Count those with the board-on-board picket count tool instead.
Formula
repeat = picket_width_in + picket_gap_in\npickets = ceil(line_length_ft × 12 ÷ repeat)\nto_buy = ceil(pickets × (1 + waste_pct))
Worked example
100 ft run, 3.5" pickets, 1.75" gap, 10% waste:
- repeat = 3.5 + 1.75 = 5.25"
- pickets = ceil(100 × 12 ÷ 5.25) = ceil(228.6) = 229
- to buy = ceil(229 × 1.10) = 252 pickets
Reference table
Pickets per 100 ft by width and gap (exact fit, before waste):
| Width | 0" gap | 1" gap | 1.75" gap | 2.5" gap |
|---|---|---|---|---|
| 3.5" | 343 | 267 | 229 | 200 |
| 5.5" | 219 | 185 | 166 | 150 |
Widths 3.5"/5.5" and gaps 0–2.5" are labeled typicals — measure your product. Your gap: 1.75".