Fence Calculator
Sources & Methodology
Posts = Perimeter / Post Spacing + 1Standard 8ft post spacing
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Fence Installation Cost Guide on CostOnce.comHow to Use the Fence Calculator
Calculate posts, rails, and pickets for your fence project. Enter your total fence length, height, and post spacing to get a complete materials list. Use our square footage calculator to determine your yard's perimeter.
Standard Assumptions
We calculate based on 8-foot post spacing (standard for most fences), with 2 horizontal rails per section. Picket count assumes standard 6-inch wide pickets with minimal gaps.
Post Depth Requirements
- Standard fences (4-6 ft): Set posts 2 feet deep
- Tall privacy fences: Set posts 2.5-3 feet deep
- Areas with frost: Below frost line (varies by region)
- Corner and gate posts: May need deeper or concrete setting
Gate Considerations
Subtract gate width from total fence length. Gates require additional hardware including hinges, latches, and often heavier posts. Plan gate locations before calculating total materials.
Related Outdoor Project Calculators
You'll need concrete for setting fence posts. For a complete backyard makeover, add mulch or gravel for landscaping. The lumber calculator helps with custom fence designs and deck railings. Finance larger projects with our loan calculator.
Frequently Asked Questions
Divide total fence length by post spacing (typically 8 feet), then add 1 for the end post. For a 100-foot fence: (100/8) + 1 = 13.5, round up to 14 posts. Add extra posts for corners and gates - each corner and gate opening needs posts.
Bury posts 1/3 of their total length, minimum 2 feet deep. For a 6-foot privacy fence, use 8-foot posts buried 2 feet deep. In areas with frost, posts should extend below the frost line (often 3-4 feet) to prevent heaving.
Divide fence length by picket width plus gap. For 3.5-inch pickets with 0.5-inch gaps, each picket unit is 4 inches. A 100-foot fence (1,200 inches) needs 1,200/4 = 300 pickets. Add 10% for waste and natural variation.
Each post typically needs 1-2 bags of 50-pound fast-setting concrete. The hole should be 3x the post width (12 inches wide for 4x4 posts) and deep enough to bury 1/3 of the post. One 50-pound bag fills about 0.4 cubic feet.
Standard spacing is 8 feet on center for most fence types, which matches standard rail lengths. Privacy fences may use 6-foot spacing for extra strength. Gate posts should be heavy-duty (6x6 instead of 4x4) regardless of spacing.
Chain link is most economical at $5-15 per linear foot installed. Wire fencing is cheapest for large areas. For privacy fencing, dog-ear pine is most affordable at $12-20 per linear foot. Prefab panels save labor over board-by-board construction.
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