NOVORY

Fence Calculator

Estimate how many fence posts, sections, and panels you need based on fence length and post spacing.

Quick answer

14 posts and 15 panels, plus about 28 bags of concrete (roughly two 50-lb bags per post hole).

Calculator

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How it works

Fence length ÷ Post spacing = Sections

The total fence length is divided by the distance between posts. Since partial sections are not possible, the result is rounded up to the nearest whole number.

Sections + 1 = Posts

Every section needs a post at each end, so the total post count is always one more than the number of sections — including the starting post.

Sections × (1 + Waste) = Panels to buy

Each section holds one panel. The panel count is increased by the waste factor and rounded up to give you the number of panels to purchase.

Worked example

A 100 ft fence with 8 ft post spacing and 6 ft height:

100 ÷ 8 = 12.5 → 13 sections

13 + 1 = 14 posts

13 × 1.05 = 13.65 → 15 panels (with 5% waste)

Buy 14 posts and 15 panels for this fence.

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A fence estimate is two numbers — posts and panels — and the post count is where estimates go wrong. It's not length divided by spacing; it's sections plus one, and every gate and corner complicates the count. Get the posts right and the panels follow.

This calculator divides your run into sections at your chosen post spacing (8 ft is the panel-fence standard), counts posts as sections plus one, and adds a waste allowance to panels for cuts and damaged boards. Concrete for the posts is a separate purchase — budget roughly two 50-lb bags per post hole.

How to measure for a fence

  1. Measure the total run in feet, then subtract gate openings — a 4-ft gate is 4 ft of fence you don't build.
  2. Set post spacing to match your panels: 8 ft is standard; don't exceed what your rails can span.
  3. Count corners and ends in your head: each needs a post, and the calculator's sections-plus-one math already covers straight runs.
  4. Keep waste at 10% for panels — boards arrive warped, split, or shorter than advertised more often than suppliers admit.

Posts & panels by run length (8-ft spacing, 10% panel waste)

RunSectionsPostsPanels to buy
50 ft788
100 ft131415
150 ft192021
200 ft252628

Sections = ceil(run ÷ spacing); posts = sections + 1; panels = ceil(sections × 1.10).

Worked example: posts & panels for 100 ft

A 100-ft straight run, 8-ft post spacing, 10% panel waste:

  1. Sections: 100 ÷ 8 = 12.5 → 13 sections.
  2. Posts: 13 + 1 = 14 posts.
  3. Panels with waste: 13 × 1.10 = 14.3 → 15 panels.

14 posts and 15 panels, plus about 28 bags of concrete (roughly two 50-lb bags per post hole).

Pro tips for fence building

  • Gates are not fence: they need larger posts (4×6 or 6×6), set deeper, with real gate hardware. Never hang a gate on a line post.
  • Bury posts at least 2 feet or below the frost line, whichever is deeper — frost heave pushes shallow posts up every winter.
  • Keep the bottom of panels 2 inches off the soil. Ground contact rots even pressure-treated lumber years early.
  • Call 811 (or your local utility locator) before you dig. Post holes and gas lines are a combination you only make once.

How to use the fence calculator

1. Choose your unit system — Imperial (feet) or Metric (meters).

2. Enter the total length of the fence you plan to build.

3. Enter the fence height — this is for reference and helps you pick the right panel size.

4. Enter the spacing between posts — typically 6 or 8 feet for residential fences.

5. Select a waste factor — 5% is common for simple runs, 10% for complex layouts.

6. Click Calculate to see the number of posts, sections, and panels you need.

How fence material is calculated

The calculator divides the total fence length by the post spacing to determine the number of sections. Since you cannot have a partial section, the result is rounded up to the nearest whole number.

The number of posts is always one more than the number of sections — one post at the start, plus one at the end of each section. The panel count equals the section count, increased by the waste factor for cuts and spares.

Why add a waste factor for fencing?

Fence installations produce waste from cuts around corners, gates, and uneven terrain. Panels can also be damaged during transport or installation. A waste factor ensures you have enough material to finish the job without a second trip to the store.

For long, straight runs on flat ground, 5% is usually enough. For fences with multiple corners, gates, or sloped terrain, use 10%.

Fence calculator example

Suppose you are building a 100-foot fence with 8-foot post spacing.

Sections: 100 ÷ 8 = 12.5 — rounded up to 13 sections.

Posts: 13 + 1 = 14 posts.

Panels with 10% waste: 13 × 1.10 = 14.3 — rounded up to 15 panels.

You need 14 posts and 15 panels for this project.

Frequently Asked Questions

How do I calculate how many fence posts I need?+
Divide the total fence length by the post spacing to get the number of sections, then add one for the starting post. For example, a 100-foot fence with 8-foot spacing has 12.5 sections — rounded up to 13 sections — requiring 14 posts (13 plus the starting post).
How far apart should fence posts be?+
Typical post spacing is 6 to 8 feet for most residential fences. Privacy fences often use 6-foot spacing for rigidity, while wire or ranch-style fences may use 8 to 10 feet. Always check your fence style and local building codes for recommended spacing.
How many fence panels do I need?+
The number of panels equals the number of sections — each section between two posts holds one panel. The calculator rounds up to a whole number and then adds a waste factor so you have material for cuts, mistakes, and future repairs.
How deep should fence posts be set?+
Posts should typically be buried at least one-third of their above-ground height, or a minimum of 24 inches — whichever is greater. In colder climates, dig below the frost line to prevent heaving. Always check local building codes for specific depth requirements in your area.
Should I buy extra fence material?+
Yes. A 5% to 10% waste allowance covers cuts, damaged panels, and posts that split during installation. Having a few extra panels also means you can match the fence later if a section needs repair.

Related Guides

How Many Fence Pickets Do I Need for 100 Feet?How Many Fence Pickets Do I Need for 200 Feet?

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