Estimate the posts, rails, pickets and concrete for a fence, whether it is a straight run or a perimeter around a rectangular property, and total up the cost.
Fence Installation Guidelines
Standard Fence Specifications:
- Post spacing: Typically 6-8 feet on center
- Post depth: 1/3 of post length (4′ fence = 6′ posts, 2′ buried)
- Concrete per post: Approximately 0.04-0.06 cubic yards
- Common heights: 4′, 6′, 8′ for residential
Fence Types & Materials:
- Wood privacy: $15-30 per linear foot
- Chain link: $8-20 per linear foot
- Vinyl: $20-40 per linear foot
- Wrought iron: $25-50+ per linear foot
Important Tips:
- Check local building codes for height restrictions
- Call 811 before digging to locate utilities
- Consider property lines and setback requirements
- Account for gates in your measurements
- Buy extra materials (5-10%) for mistakes and future repairs
What this fence calculator does
- Linear Fence: posts, sections, rails and concrete for a straight run, from the length, post spacing and rails per section.
- Perimeter: the fence length around a rectangle after taking out gates, with a post count that includes gate posts.
- Picket Fence: the number of pickets from the picket width and the gap between them, plus posts and rails.
- Cost Estimator: material and labour per linear foot, posts, and any additional costs.
How it is calculated
- Posts for a straight run = length ÷ post spacing (rounded up) + 1. Sections = posts − 1, and rails = sections × rails per section.
- Perimeter fence length = 2 × (length + width) − the gate widths. Posts = fence length ÷ spacing (rounded up) + 1, plus 2 for each gate.
- Pickets = fence length in inches ÷ (picket width + gap), rounded up.
- Concrete assumes 0.05 cubic yards per post.
Worked examples: 100 ft at 8 ft spacing with 3 rails needs 14 posts, 13 sections, 39 rails and about 0.70 cubic yards of concrete. A 100 ft × 50 ft perimeter with one 4 ft gate needs 296 ft of fence and 40 posts. 50 ft of fence with 5.5 inch pickets and 0.5 inch gaps needs 100 pickets. Costing 100 ft at $15 material and $10 labour per foot, plus 14 posts at $25 and $200 of other costs, comes to $3,050, or $30.50 per foot.
Things to keep in mind
The post counts follow simple rules (sections + 1, and 2 extra per gate), so a layout with unusual corners or spacing may need a different number. Buy a few percent extra pickets for cuts and replacements, and remember that posts are longer than the fence height because part of each post is buried. These are planning estimates only. Measure your own project carefully, check product labels and local building codes, and confirm quantities with your supplier or a qualified contractor before you buy.
Frequently asked questions
Does the perimeter calculator include corner posts?
The post count is sections plus one, plus two for each gate. Check it against a sketch of your own layout.
Can I leave the gap between pickets at zero?
Yes. A gap of 0 inches means the pickets sit edge to edge.
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