フェンス縦板計算ツール

Picket count comes from one formula: divide the usable run, in inches, by the picket pitch, the board width plus whatever gap sits between boards, then round up and add a waste allowance. A zero gap, as on a butted privacy fence, gives the highest count for a given board width; a visible gap, as on a classic picket fence, lowers it; and an overlapping layout tightens the pitch below the board's own width and raises it again. This calculator is the single-purpose version of that formula, useful for checking a lumber order against a quote or against the fuller wood fence calculator, which runs the same math alongside posts and rails.

Gate openings matter before the division happens, not after. This calculator subtracts any gate width from the run first, so a 4 foot walk gate does not silently inflate the picket total for a stretch of fence that is not covered in pickets at all. Skipping that step is one of the more common ways a hand calculation comes out high, and it gets worse on a run with more than one gate.

A waste factor sits on top of the pitch math, typically around 10 percent, to cover cut ends at corners and the occasional warped or split board rejected on site. A simple straight run with no corners can run a lower waste allowance; an irregular boundary with several turns usually warrants more. Once the picket count is settled, the fence rail calculator handles the horizontal backer boards the pickets attach to, and the fence post calculator covers the posts those rails span between, the other two legs of a complete wood fence take-off.

For a worked example at common board widths, how many pickets for 100 feet of fence walks through the arithmetic step by step. Once materials are counted, the fence cost calculator turns the picket, rail and post counts into a total using your own local prices, and the wood fence installation guide covers how pickets actually get attached to the rails once the count is in hand.

Board-on-board layouts use a different version of this same formula: instead of adding a gap, the overlap between boards is subtracted from the width, which produces a smaller effective pitch and a correspondingly higher picket count for the same run. That distinction matters when comparing a quote across styles, since a board-on-board estimate that uses the plain width-plus-gap formula instead of accounting for the overlap will come in short of what the job actually needs.

Board width itself is worth measuring rather than assuming, since nominal lumber sizes do not always match actual milled width, and a half-inch difference compounds meaningfully over a long run. A 1x6 board, nominally 6 inches, is commonly milled to about 5.5 inches actual width, and a 1x4 to about 3.5 inches; entering the real measured width rather than the nominal size is what keeps the picket count accurate against what actually gets delivered.

Corner posts affect picket layout even though they do not change the total count: the last picket before a corner post often needs a slightly narrower rip cut to land the pattern correctly, which is a layout detail rather than something that adds boards, but it does mean the final board on each section is rarely a full-width piece straight off the stack. Planning for that cut, rather than discovering it while standing at the corner with a full board in hand, is part of what separates a tidy finished run from one with visibly uneven end pickets.

It is also worth ordering slightly more boards than the bare computed total even after the waste factor is applied, since matching stain or paint on a single replacement board months or years later rarely comes out identical to the weathered boards around it. Keeping a small reserve bundle of the same batch, cut from the same run of lumber, is a common practice among installers for exactly that reason, separate from the waste allowance this calculator already includes for cutting losses during the original installation.

Picket thickness, not just width, is worth noting when ordering, since a nominal 1 inch board is commonly milled to about 3/4 inch actual thickness, and that thickness affects fastener length and the overall look of the fence face rather than the picket count itself. Two fences built to the same width and gap can still look different if one uses thicker stock, which is a design preference separate from the quantity this calculator returns.

Delivery logistics are also worth planning around picket count rather than leaving until the last step: a large order of 1x6 boards for a long run is heavy and bulky enough that many suppliers deliver by the pallet rather than as individual boards, and confirming pallet quantities against the computed picket count avoids ordering in an awkward in-between amount that leaves either a wasted partial pallet or a shortfall.