How to use this calculator
- Enter the fence run. Use the total planned fence length before subtracting gate openings.
- Set gates and spacing. Enter gate count, gate width, maximum post spacing and rails per section.
- Enter picket and concrete assumptions. Use actual picket width, gap, waste, post-hole diameter, depth and concrete bag yield.
- Read the takeoff. Use pickets, posts, rails, sections, concrete bags and estimated cost as a planning estimate.
How it works
This wood fence material calculator treats the fence as a straight linear run with gate openings removed from the picketed length.
picketed_length = fence_length - gate_count x gate_width
sections = ceil(picketed_length / post_spacing)
posts = sections + 1 + 2 x gate_count
Pickets are counted from their installed coverage, then rounded up after waste:
picket_coverage = picket_width + picket_gap
pickets = ceil(((picketed_length + gap) / picket_coverage) x waste_factor)
Concrete is a cylindrical post-hole volume for each post, divided by the entered bag yield.
Worked example
Verified against the live calculator
A 100 ft fence run with one 4 ft gate leaves
96 ft of picketed fence. At 8 ft post spacing,
the layout has 12 sections, 15 posts after the
gate-post allowance, and 36 rails when each section uses
three rails. With 5.5 in pickets, a 1/8 in gap
and 10% waste, the takeoff rounds up to
226 pickets.
Frequently asked questions
How do you calculate wood fence materials?
Subtract gate openings from the total run, divide the remaining length by post spacing for fence sections, then count posts, rails and pickets. Pickets are based on picket width plus gap, with waste added and rounded up.
Do gates change the picket count?
Yes. Gate openings are deducted from the picketed fence length. The calculator also adds two gate posts per gate, but it does not estimate gate frames, hinges, latches or diagonal bracing.
How much concrete do fence posts need?
The calculator treats every post hole as a cylinder: volume is pi times radius squared times depth, multiplied by the post count. Bag count is concrete volume divided by bag yield, rounded up.
Is this a fence design calculator?
No. This is a material takeoff for posts, rails, pickets and concrete. Wind load, frost depth, soil, post embedment, gate hardware, permits and local code still need a separate check.
Method & assumptions
- Linear fence material takeoff only; corners, stepped panels, sloped terrain and nonuniform bays need a field layout.
- Gate openings are deducted from the picketed length and add two posts per gate. Gate frames, hinges, latches, handles and diagonal bracing are not included.
- Post holes are modeled as round concrete cylinders with the same diameter and depth for every post.
- Board-on-board, shadowbox, lattice top, cap boards and trim boards need separate allowances beyond the picket count shown here.
- For exact fence search paths, use the fence calculator, fence material calculator or wood fence calculator.
- Use deck board, deck footing concrete and wood span tools for adjacent deck and framing takeoffs.