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Fence Calculator

Plan your fence project with confidence. Enter your fence line length, choose your height and style, and this calculator instantly estimates how many posts, rails, pickets, and bags of concrete you'll need — plus a total material cost. Works for wood privacy fences, picket fences, and shadowbox styles.

Total linear feet of fence line
Standard dog-ear picket: 5.5" (actual)
0" = privacy fence; 1–2" = spaced picket
$12–18 for pressure-treated pine, $20–35 for cedar. Includes posts, rails, pickets, concrete, and hardware.

📊 Fence Material Estimate

Fence Length—
Fence Height—
Posts Needed—
Sections—
Rails Needed (Total)—
Pickets Needed—
Concrete Bags (50 lb)—
Estimated Total Cost—
Includes a 10% waste factor for pickets and rails. Post count includes end/corner posts. Concrete estimate: 2 bags per post for 6-ft fence, 3 for 8-ft.

How to Use the Fence Calculator

Start by measuring your total fence line in linear feet. Walk the property line with a measuring wheel or tape — don't forget to account for gates (subtract gate width from the total, as gates use their own hardware). Enter the length into the calculator along with your desired fence height.

Post spacing is typically 8 feet on center for wood fences, but you can tighten to 6 feet for extra wind resistance or heavier gates. More posts means a stronger fence but higher cost. The post count formula is length ÷ spacing + 1, which gives you one post at the start and one at each interval.

Rails are the horizontal members that run between posts. A 4-foot picket fence usually takes 2 rails. A 6-foot privacy fence can use 2 or 3 rails (3 is better for preventing sag). An 8-foot fence should always use 3 rails. Each rail is typically a 2×4 that spans the full post spacing.

Pickets are calculated based on their actual width plus any gap. For a standard privacy fence, use 5.5-inch pickets with 0-inch gap (tight-fit). For a spaced picket fence, add a 1–2 inch gap for that classic look. The calculator adds 10% extra for waste, cut-offs, and damaged boards.

Concrete: Each post hole takes roughly 2 bags of 50 lb fast-setting concrete mix for a 6-foot fence (hole: 12" diameter × 30" deep). Adjust to 3 bags for 8-foot posts. The calculator multiplies post count by the appropriate bag factor.

Fence Building Tips

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📚 Industry Resources & Standards

Home Depot - Fence Guide

This Old House - Fencing

Frequently Asked Questions

Divide your total fence length by your post spacing (typically 8 feet), then add 1 for the starting post. For example, a 100-foot fence with 8-foot spacing needs 100 ÷ 8 + 1 ≈ 14 posts. Corner posts count in both directions — if your fence turns a corner, you'll need a post at each turn. Our calculator handles this math automatically.
For a standard 4×4 post set 30 inches deep in a 12-inch diameter hole, you need approximately 2 bags of 50 lb fast-setting concrete mix. For 8-foot tall fences with deeper holes (36–42 inches), plan on 3 bags per post. Some contractors use 60 lb bags — one 60 lb bag is equivalent to about 1.2 fifty-pound bags. Always have an extra bag or two on hand.
Materials for a pressure-treated pine privacy fence run $12–18 per linear foot (DIY). Cedar runs $20–35 per linear foot. Vinyl fencing materials are $25–40 per linear foot. Professional installation adds $15–30 per linear foot, bringing most installed wood fences to $30–55 per linear foot total. These are 2026 averages — prices vary by region and lumber market conditions.
Two rails are standard for 4-foot fences and acceptable for 6-foot fences in low-wind areas. Three rails are strongly recommended for 6-foot fences in windy regions and required for 8-foot fences. The third rail — placed in the middle — prevents picket warping, sagging, and blow-out. The extra cost is minimal (about $2–3 per linear foot) and significantly extends fence life.
Subtract the gate width from your total fence length. A standard walk gate is 4 feet wide; a double drive gate is 10–12 feet. Gate posts need to be heavier — use 6×6 posts instead of 4×4 and set them deeper with extra concrete. Gates don't need pickets or rails from the fence budget since they're built separately, but you'll need gate hardware (hinges, latch, handle) which adds $30–80 per gate.