Fence Calculator
Estimate posts, panels or pickets, and optional post-hole concrete.
Your project
Enter your measurements. Required fields are labeled; assumptions and optional quotes can be edited below.
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How this calculator works
Describe one continuous open path as ordered solid sections and gate openings. Split at every corner. Every entered span is post-center to post-center; adjacent rows share exactly one endpoint post. For a gate measured as a rough clear opening, add the two post half-widths and any hardware allowance supplied by your installer. No gate length is automatically deducted from a solid row. One to thirty rows are supported and at least one must be solid.
For each solid: bays = ceil(span / max bay), actual equal pitch = span / bays > post width. Posts = sum(solid bays) + gate openings + 1. Panel purchase = ceil(bays × (1 + infill allowance)). Pickets/bay = ceil((pitch − post width + gap) / (picket width + gap)); sum actual per-bay counts before allowance. Base rail pieces = bays × rails/bay.Panel systems must fit or be cut to each resulting bay. Enter the effective installed maximum center pitch, rather than assuming advertised panel width equals that pitch. Panels already contain their rails, so panel mode has no separate rail count or cost. Picket edge pieces may need cutting. Picket and panel prices are independent. A gate adds one opening and one endpoint, with no infill bay. Corners share a post; adjacent gates also share the intermediate post but require separate post/footing design. No last-to-first loop closure is inferred.
Optional concrete includes every counted post. Base volume = posts × (π × hole diameter² / 4 − square post width²) × actual filled height. The hole diameter must exceed the post diagonal, post width × √2. Apply the separate concrete allowance, then bags = ceil(adjusted volume / labeled yield). Enter actual fill height excluding gravel and unfilled top. A bag sold only by weight requires its stated volume yield. Disabling concrete excludes its geometry, prices and outputs.
Assumptions and limitations
One ordered open path; adjacent rows share one endpoint. No loop closing or post allowance. Rail quantities are bay-length pieces, not stock-board optimization or fastening approval. Concrete uses user-supplied geometry only; no frost depth, hole sizing, gate footing design or structural adequacy is inferred.
US/Metric changes representation only, including inactive fields. Explicit US-market and Metric-market presets change their listed assumptions, never project measurements. Assumptions are editable planning inputs. Required project measurements start blank; calculate explicitly before valid edits update the estimate.
Allowance is the added requirement before whole-item purchase rounding; purchase rounding surplus is separate. Only active supplied prices enter cost. Missing is unpriced, while an entered zero is a valid price. A partial priced list names how many active material types are priced.
Worked examples
FENCE-01: Panels with solid 24 ft, gate 4 ft and solid 16 ft; max bay 8 ft, actual post 3.5 in, 10% infill allowance, concrete off. The two solid sections have 3 + 2 = 5 bays. One gate gives 7 posts. Five base panels become 6 purchased panels; total path is 44 ft. At $20/post, $50/panel and $100/gate opening kit, subtotal is $540.00. There is no separate rail line.
FENCE-02: One solid 16 ft section, max bay 8 ft, actual post 3.5 in, picket 5.5 in, gap 0.125 in, two rails/bay and 10% infill allowance. Two bays each have 92.5 in clear width and 17 pickets: 34 base / 38 purchased pickets; 4 base / 5 purchased bay-length rail pieces; 3 posts. With 12 in holes, 24 in actual fill height, 0.5 ft³/bag and 0% concrete allowance, base concrete is 4.2019723137 ft³ and 9 bags. At $20/post, $3/picket, $8/rail piece and $7/bag, subtotal is $277.00.
Confirm actual bay fit, fastening/cut lengths, gate hardware and user-supplied hole geometry before shopping.