Fence Materials Calculator
Count the posts, rails and pickets a fence run needs from its length, post spacing, rails per section and picket size.
Posts, rails and pickets for the fence.
How the fence materials calculator works
A fence is a run of sections between posts: sections = length ÷ post spacing, rounded up; posts = sections + 1; rails = sections × rails per section. Pickets fill the length: length ÷ (picket width + gap). Corners and gates each add a post.
Standard post spacing is 2.4 m (8 ft) for timber; 2.7 m with steel posts. Three rails suit fences over 1.5 m tall, two below.
Formula: sections = ⌈length ÷ spacing⌉ · posts = sections + 1 · pickets = ⌈length ÷ (picket width + gap)⌉
Worked examples
| Inputs | Posts | Note |
|---|---|---|
| 30 m at 2.4 m spacing, 3 rails | 14 | 13 sections, 14 posts, 39 rails |
| 30 m at 2.4 m, 90 mm pickets with 10 mm gaps | 14 | 300 pickets |
| 100 ft at 8 ft spacing, 2 rails | 14 | 13 sections, 14 posts |
FAQFrequently asked questions
How far apart should fence posts be?
2.4 m (8 ft) is standard for timber rails; up to 2.7 m with steel posts and rails. Closer spacing in high-wind areas.
How many rails do I need?
Two for fences up to about 1.2 m, three for 1.5–1.8 m, four above that. Rails are usually 2.4 m or 3.6 m lengths.
Does the calculator count corners and gates?
Add them as extra posts in Detailed mode: one per corner, two per gate.
How much concrete do the posts need?
Use the post-hole concrete calculator with the post count from here.
Where these figures come from
- The Engineering ToolBox — material densities, coverage and unit data — bulk densities, concrete at 2,400 kg/m³, board and sheet sizes
- Gypsum Association — gypsum board sizes — 4 × 8 and 4 × 12 ft sheets
- ADA Standards for Accessible Design — ramps (§405) — maximum running slope 1:12
- International Code Council — the International Residential Code
Last checked: September 2026. Coverage rates and material sizes are typical manufacturer figures — check the product you buy.