TwoCut Tools · Material planning

Fence Picket & Gate Planner

Plan different clear spans, choose end clearances, and combine picket packages and factory gates in one purchase list.

Illustrative inputs are editable. Read the method and confirm the actual product label before buying.

Project inputs

Enter each actual post-to-post span and factory gate separately, specifying units and measured widths.

Calculation limits

Up to 1,000 separate spans and factory gate openings are supported. Keep each measured post-to-post span separate. For larger jobs, add unrounded picket quantities across plans, then round purchase packages once.

Numeric inputs are limited to 10,000,000 in the selected units. Positive dimensions and coverage must be at least 0.000000000001. Whole-package rounding only tolerates floating-point noise at nonzero integer boundaries.

Method, product inputs & limits

This is a single-layer, full-width picket layout between measured post faces. A gate row represents one factory gate leaf; it contributes no pickets. Split left and right spans into separate rows rather than subtracting a gate from a continuous run.

Our own geometric derivation: equal-end mode uses L = n·w + (n+1)·g, so n = max(1, ceil((L−gmax)/(w+gmax))) and actual g = (L−n·w)/(n+1). Fixed ends use U=L−2e, n = ceil((U+gmax)/(w+gmax)), then g=(U−n·w)/(n−1). A single picket must exactly fill U in fixed mode. Infeasible full-width layouts are rejected. The selected maximum gap is a design input, not a code or safety limit.

The manufacturer distinguishes fence styles and supplies 7 pickets in the documented kit. Its nominal 1×4 size is not an actual-width promise. Example dimensions are illustrative measured inputs, not a product preset. The PDF does not publish our equal-gap formula. Posts, rails, footings, hinges and fasteners require the chosen system’s own instructions and are outside this picket/gate list.

Primary sources & calculation review

Reviewed 2026-10-12 by TwoCut Tools using Codex. Manufacturer instructions support the product context; our derived geometry and rounding are identified separately. No manufacturer endorsement or installer review is claimed.

Two distinct worked decisions

Plan before you buy

Calculation notes reviewed October 23, 2026. Examples use the mathematical model in this calculator.

How to use this calculator

  1. Measure each clear span between the boundaries that will hold the pickets. Enter actual picket width and maximum gap in inches or millimeters.
  2. Choose equal gaps at both ends or a fixed end clearance. Mark factory gate openings as gates so they do not also receive pickets.
  3. Combine installed pickets, add the chosen spare count and round once to your package size. Confirm gates, posts and fasteners separately.

Formula and rounding

Equal-end mode uses n = ceil((clear span − maximum gap)/(picket width + maximum gap)), with at least one picket. Actual gap = (span − n × width)/(n + 1). Fixed-end mode first subtracts twice the end clearance, then fits n pickets with n − 1 interior gaps. The model rejects overlaps and gaps larger than your maximum. Packages = ceil((installed pickets + spares)/pickets per package).

Example 1: Equal gaps in a 96-inch opening

Enter a 96 in span, 3.5 in actual pickets and a 3.5 in maximum gap. Equal ends give ceil((96 − 3.5)/7) = 14 pickets. Fifteen gaps each measure (96 − 49)/15 = 3.1333 in. With 7 pickets per package and zero extra pickets, buy 2 packages.

Example 2: Zero end clearance changes the package count

Use the same span and widths, but select fixed ends with 0 in clearance. Count = ceil((96 + 3.5)/7) = 15 pickets. Fourteen interior gaps each measure (96 − 52.5)/14 = 3.1071 in. At 7 per package, ceil(15/7) = 3 packages, supplying 21 pickets. The 6 extras arise from package rounding, even with the spare input at zero.

Common mistakes to avoid

Questions before ordering

Does this choose legal fence gaps?

No. You enter the limit. Pool barriers, guardrails and other regulated uses need their own applicable requirements.

Does it include posts and rails?

No. The purchase plan covers full-width pickets and factory gate leaves, not a structural fence design.

Can I rip the last picket to fit?

This model uses full-width pickets and equal internal gaps. A layout requiring ripped pickets must be planned separately.

Are gate clearances automatic?

No. Verify the gate supplier's opening, hinge and latch clearances. A gate row counts one leaf and no pickets.

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