ewory.com logo

Fence Calculator

Enter the total fence length, post spacing, and panel width. The calculator shows posts, panels, and concrete bags needed.

Fence Posts Needed

Fence Panels Needed

Concrete Bags (1 per post)

How the Fence Calculator Works

Planning a new fence requires knowing how many posts, panels, and bags of concrete you need before heading to the hardware store. This calculator takes your total fence perimeter, post spacing, and panel width to give you accurate material estimates. Enter your numbers and instantly get a shopping list for your fencing project.

Fence Material Formulas

Posts = (Total Length ÷ Post Spacing) + 1

Panels = Total Length ÷ Panel Width

Concrete Bags = Number of Posts × 1 bag per post

One 50–60-lb bag of fast-setting concrete (like Quikrete Fast-Setting) is sufficient for a standard 4×4 post set in a hole 10 inches wide and 24–36 inches deep. Larger posts or deeper holes require 2 bags per post.

Worked Example

You want to fence a rectangular yard: 60 ft × 40 ft perimeter = 200 total feet

  • Post spacing: 8 feet
  • Panel width: 8 feet

Results:

  • Posts: (200 ÷ 8) + 1 = 26 posts
  • Panels: 200 ÷ 8 = 25 panels
  • Concrete bags: 26 × 1 = 26 bags

Add 1–2 extra posts for corners and gate installations.

Fence Types and Materials

The type of fencing you choose affects materials, costs, durability, and maintenance requirements significantly. Here is a comparison of the most common residential fence types:

Fence TypeCost per Linear FootLifespanMaintenance
Wood privacy fence$15–$3515–20 yearsStain/seal every 2–3 years
Vinyl (PVC) fence$20–$4525–30 yearsMinimal — rinse with hose
Chain-link fence$10–$2020–30 yearsVery low
Aluminum fence$25–$4030+ yearsVery low — no rust
Wrought iron fence$25–$7550+ yearsPaint every 5–10 years
Split rail fence$10–$2510–20 yearsLow

Post Spacing Guidelines

Post spacing affects the structural strength and appearance of a fence. Standard spacing varies by fence type:

  • Wood privacy fence: 6–8 feet on center
  • Chain-link fence: 6–10 feet on center
  • Vinyl fence: 6–8 feet on center
  • Aluminum/wrought iron: 6–8 feet on center
  • Split rail fence: 8–10 feet on center

Closer post spacing (6 feet) creates a stronger, more rigid fence. Wider spacing (8–10 feet) uses fewer materials but may flex in wind or under snow load.

Setting Fence Posts

Proper post installation is critical for fence longevity. The most common failure point for wooden fences is post rot at ground level. Best practices include:

  • Post depth: Bury at least 1/3 of the total post length underground (a 6-ft post needs a 2-ft hole minimum)
  • Frost line: In cold climates, posts must be set below the local frost depth to prevent heaving
  • Concrete: Use fast-setting concrete for convenience; mix ratio doesn't matter as much as coverage
  • Gravel base: Add 3–4 inches of gravel at the bottom of post holes to improve drainage and reduce rot
  • Post treatment: Use pressure-treated lumber or naturally rot-resistant woods (cedar, redwood) for posts

Gate Planning

Every fence needs at least one gate for access. Standard gate openings:

  • Walk-through gate: 36–42 inches wide (minimum ADA width is 32 inches)
  • Double drive gate: 10–12 feet wide for vehicle access
  • RV gate: 12–14 feet wide

Gates require extra post reinforcement. Use 4×6 or 6×6 posts at gate openings and set them deeper than standard posts. Gates add weight and stress to posts over time, so quality hardware and proper installation are essential.

Frequently Asked Questions

How many fence posts do I need for 100 feet?

For 100 linear feet with 8-foot post spacing, you need 13 posts (100 ÷ 8 = 12.5, rounded up to 13, plus 1 for the end = 14 posts). Always add extra for corners and gates.

How deep should fence posts be set?

A general rule is to bury at least 1/3 of the post's total length. A 6-foot fence typically uses 8-foot posts set 2 feet deep. In cold climates, set posts below the frost line to prevent heaving.

Do I need a permit to build a fence?

Most municipalities require a permit for fences above 6 feet. Many HOAs also have restrictions on fence height, style, and placement. Always check local ordinances before starting your project.

How many fence boards do I need for a privacy fence?

This depends on board width. For a standard 6-inch wide board with a 1/4-inch gap, you need approximately 2 boards per linear foot. For 100 linear feet, that's about 200 boards at 6 feet tall.

What is the best fence for privacy?

Board-on-board or tongue-and-groove wood privacy fencing provides maximum visual blocking. Vinyl privacy panels are an alternative with less maintenance. Fences should be at least 6 feet tall for privacy in most residential settings.

Related Tools

Sources