Fence Materials Calculator
The Fence Materials calculator shows the post count, panel count, and concrete bags you’ll need for a straight run—factoring in post spacing, panel width, and gates.
We let you enter total run length, choose your post spacing and panel width, and add gate count. We’ll compute how many posts to set (including an extra allowance for gates), how many pre-built panels to buy, and an estimate of concrete bags based on typical hole size and bag volume. Use this to plan purchases or to sanity-check quotes; if you want to do the math manually, we outline the steps below.
Enter the run length, choose post spacing and panel width, and add gate count. We’ll estimate posts (with an extra allowance for gates), panels to buy, and concrete bags using your hole size and bag weight.
Common: 6–8 ft for wood privacy fences.
Pre-built panels often come in 6 ft or 8 ft widths.
We add ~1 extra post per gate.
Estimates assume a straight run. For corners/changes of direction, add one post per corner. Check local code and frost depth for hole sizing.
Results interpretation
How it works
We turn your run length, spacing, and panel width into simple counts, then size concrete using a cylindrical hole model.
Formulas, assumptions, limitations
Base posts. ceil(Run ÷ Spacing) + 1 (posts at both ends).
Gate posts. Add ~1 extra post per gate; many gates reuse one line post.
Panels. ceil(Run ÷ PanelWidth). Works for pre-built wood/vinyl panels.
Concrete. Hole volume = π × (diameter/2)² × depth (feet). Bags/post = ceil(HoleVolume ÷ BagVolume).
Corners. Add a post for each outside corner or sharp change in direction.
Use cases & examples
Base posts = ceil(200/8)+1 = 26. Gate allowance +2 → 28 posts. Panels = ceil(200/8) = 25. With 8×24 in holes and 60 lb bags (~0.45 ft³), per-post volume ≈ 0.87 ft³ → 2 bags/post; total ≈ 56 bags.
Base posts = ceil(120/6)+1 = 21. Panels = ceil(120/6) = 20. 8×30 in holes with 80 lb bags (~0.60 ft³) → per-post ≈ 1.05 ft³ → 2 bags/post; total ≈ 42 bags.
Base posts = ceil(300/10)+1 = 31. +1 gate → 32 posts. Panels = ceil(300/8) = 38. 10×24 in holes, 50 lb bags (~0.37 ft³) → per-post ≈ 1.36 ft³ → 4 bags/post; total ≈ 128 bags.
Fence materials FAQs
Why add an extra post per gate?
A gate needs two posts (hinge and latch). One usually overlaps with the run, so we add ~1 extra post per gate as a simple planning rule.
Do I need more posts for corners?
Yes. Add one post for each outside corner or direction change. For complex layouts, estimate runs per segment.
How deep should fence posts be?
Depth depends on frost line and local code. A common rule is at least 1/3 of post length in the ground—verify locally.
Are panel and spacing values required to match?
They can differ. Panels determine how many pre-built sections to buy; spacing determines post count and may vary with terrain.
How many concrete bags per post?
It depends on hole size and bag volume. Our calculator shows bags per post and totals after rounding up.
What about rails and pickets?
This tool focuses on posts, panels, and concrete. For stick-built picket fences, use manufacturer coverage tables to estimate picket count.
Planning a fence the practical way
Materials estimating should be fast and repeatable. We turn the essentials—run length, spacing, panel width, and gates— into a reliable list you can price out today. As you refine the layout, adjust spacing or gate count and watch the results update instantly.
Posts: the backbone of the line
Posts anchor the structure and set the rhythm of the fence. Tight spacing improves rigidity in wind and uneven terrain, while wider spacing saves posts but demands stronger rails and panels. Many residential wood fences land between 6 and 8 feet on center.
Panels vs. stick-built sections
Pre-built panels reduce labor but lock you into fixed widths. Stick-built fences offer more flexibility with terrain and obstacles. Our panel count is a quick purchase plan; if you’re stick-building, treat it as the number of panel-equivalents along the run and purchase pickets/rails accordingly.
Concrete: sizing holes with simple geometry
We approximate each hole as a cylinder. Converting inches to feet, we compute volume and round up bags per post based on your bag size. It’s smart to buy an extra few bags to cover over-excavation or soil collapse.
Layout tips
- Pull a string line and mark post centers before digging.
- Start at corners and gates, then infill intermediate posts.
- Check local codes and HOA rules for height, style, and setback.
- Call utility-locating services before digging.
- Use a level and braces to hold posts plumb while concrete cures.
Budget and contingencies
Material costs fluctuate with lumber and cement markets. Build a 5–10% buffer for overruns, and consider weather delays for curing time. Accurate counts upfront reduce return trips and speed up installs.
From estimate to order
Once you’ve dialed in spacing and gates, save a shareable link and send it to suppliers. Ask them to confirm lead times, delivery, and any bulk pricing. If you expect corners or elevation changes, include a rough sketch.