Fence & Railing Material Calculator Guide
Enter the total fence length, post spacing, post height above grade, and the number of horizontal rails. The calculator returns the total number of posts and linear footage of material needed, plus a 10% overage estimate for cuts and waste.
How Posts Are Counted
Posts = ceiling(total length รท post spacing) + 1. This includes both end posts. Example: 100 ft fence at 6 ft spacing = 17 posts. Corner and gate posts are not automatically added โ add those separately.
Building Code Notes
Residential guardrails in the US (IRC) must be at least 36 in high for decks under 30 in off the ground, and 42 in for higher decks. Commercial guardrails follow IBC at 42 in minimum. Always verify local requirements before building.
Frequently Asked Questions
17 posts ร 6 ft = 102 ft of post material. 100 ft ร 3 rails = 300 ft of rail. Total = 402 ft, with 10% overage = 442 ft.
A common rule: bury at least 1/3 of the total post length. For a 6 ft fence with 8 ft posts, bury 2โ2.5 ft. Deeper frost zones may require deeper holes.