How many pickets do I need for 100 feet?

For 3.5" boards with a 1.75" gap it is ceil(100 × 12 ÷ 5.25) = 229 pickets (about 252 with 10% waste). Butted 5.5" boards need about 219; the exact number depends on your board width and gap.

Does a bigger gap use fewer pickets?

Yes. The gap adds to the pitch in the denominator, so widening it lowers the count. Going from a butted 3.5" board to a 1.75" gap drops a 100 ft run from 343 to 229 boards.

Why does board-on-board need more pickets?

Board-on-board and shadowbox overlap each board, so the coverage per board is width − overlap instead of the full width — about a third more boards. Use the board-on-board picket count.

Should I round the picket count up?

Always — you cannot buy a fraction of a board, so the formula uses ceil(). Then add ~10% for waste, off-cuts and corners.

How many pickets for 100 feet of fence?

The number of pickets in a run has nothing to do with the posts and everything to do with picket width and the gap between boards — two boards of the same length can differ by a third depending on how they’re spaced.

By Francesco Zinghinì

Pickets are the vertical boards that fill the fence face. Because they repeat at a fixed pitch, the count is a clean division once you know two measurements: the board’s width and the gap you leave between boards.

The formula

Each picket “consumes” its own width plus one gap of the line:

pitch = picket width (in) + gap (in)
pickets = ceil(line × 12 ÷ pitch), then × (1 + waste%).

Multiply the length by 12 to convert feet to inches, divide by the pitch, and round up. Then add ~10% for waste, off-cuts, corners and the odd cracked board. The picket / board count calculator does this and reports both the exact and the with-waste count.

Worked examples for 100 feet

Nominal boards are usually 3.5" or 5.5" wide; gaps range from 0 (butted) to about 2.5":

3.5" pickets, 1.75" gap: pitch 5.25" → ceil(100 × 12 ÷ 5.25) = ceil(228.6) = 229 pickets; with 10% waste, 252.
3.5" pickets, no gap: pitch 3.5" → ceil(1200 ÷ 3.5) = 343 pickets.
5.5" pickets, 1.75" gap: pitch 7.25" → ceil(1200 ÷ 7.25) = 166 pickets.
5.5" pickets, no gap: pitch 5.5" → ceil(1200 ÷ 5.5) = 219 pickets.

The pickets-per-100-ft table lays out these combinations so you can look up your board and gap at a glance.

Butted, spaced, board-on-board and shadowbox

The gap you choose sets the look and the count:

Spaced picket: a positive gap (often 1.75–2.5") for a classic open picket fence.
Butted privacy: gap 0 for a solid face — the most boards of the flat styles.
Board-on-board / shadowbox: boards overlap, so coverage per board is width − overlap. That needs about a third more boards — use the board-on-board picket count. For example, 100 ft of 5.5" boards with a 1" overlap gives an effective 4.5" coverage → ceil(1200 ÷ 4.5) = 267 boards, versus 219 butted.

Why the gap matters so much

Because the pitch sits in the denominator, small gap changes move the count a lot. Widening the gap on 3.5" boards from 0 to 1.75" drops a 100 ft run from 343 to 229 boards — a third fewer — while narrowing the gap fills the face and raises the count. It also affects privacy: a solid, no-gap face blocks the most sightline, while a spaced picket is decorative. Decide the look first, then let the formula give the count.

Don’t forget rails, backers and fasteners

Pickets don’t stand alone — they nail to horizontal rails. A 4 ft fence usually runs 2 rails, a 6 ft fence 3 rails, so a 100 ft, 6 ft fence at 8 ft spacing is ceil(100 ÷ 8) = 13 sections × 3 = 39 rails; the rail calculator counts them. Budget fasteners too: at two or three screws or nails per picket per rail, a 6 ft picket takes 6–9 fasteners, so a few hundred boards is well over a thousand fasteners. Board-on-board and shadowbox fences may also need a backer rail or nailer that a simple butted fence does not.

Estimating a whole yard

For a full perimeter, split it into straight runs, count pickets per run and add them — gates interrupt the picket line, so subtract the gate openings from the picketed length (the gate itself is built as its own small panel). If you only know the yard size, turn area into perimeter first with the cost-to-fence-an-acre tool, then feed that length into the picket formula.

Measure your actual board

“3.5 inch” and “5.5 inch” are nominal widths; a real board can run slightly under. Because you multiply across a long run, a small width error compounds into several boards, so measure the actual product and use that number. Widths and gaps here are labeled typicals — confirm on your material and order ~10% extra.

Cap rail, trim and the finished look

The picket count fills the field, but a finished fence often adds trim the raw formula doesn’t: a top cap rail running over the picket tops (ties the run together and protects end grain), a kickboard or rot board along the bottom (keeps pickets off the soil and closes the gap on a stepped slope), and post caps. None of these change the picket count, but they are separate material bought by the linear foot or by the post, so put them on the list next to the pickets. Picket tops are a style choice too — flat-top, dog-ear, gothic or French gothic — and while the profile doesn’t change the count, pre-cut tops save a lot of cutting. Decide the trim and top style before you order so the cap and kickboard lengths are counted with everything else.

This is a material-quantity guide, not a bid. Confirm picket dimensions on your product, choose your gap for look and privacy, and order a little extra for waste and corners.