Fence Calculator — How Much Fencing Do I Need?
Enter your fence length, post spacing, and picket size to get the exact number of posts, rails, and pickets. No sign-up, no data stored.
Fencing materials
How fencing quantity is calculated
The math is simple and exact — no assumptions to adjust for:
- Posts = fence length ÷ post spacing, rounded up, + 1 for the corner or end post.
- Rails = rails per section × the number of sections, where each section is one rail length. Rails run the full fence length, split into standard boards.
- Pickets = fence length in inches ÷ (picket width + gap), rounded up.
Add a few extra posts and pickets for gates, corners, and waste. Gates need heavier posts on both sides of the opening, so subtract the gate width from the picket count and add posts separately.
Fence material chart
Standard post spacing, rail counts, and picket spacing.
Post spacing by fence type
| Fence type | Recommended spacing |
|---|---|
| Light / decorative | ~8–10 ft |
| Standard wood picket | ~8 ft |
| Tall / windy area | ~6 ft |
| Heavy / gate support | ~4–6 ft |
Rails by fence height
| Fence height | Typical rails |
|---|---|
| 3–4 ft | 2 rails |
| 5–6 ft | 3 rails |
| 6 ft+ (board on board) | 3–4 rails |
Picket spacing (1×6 pickets, 5.5" wide)
| Gap | Look | Pickets per 10 ft |
|---|---|---|
| 0" | Board on board | ~22 |
| 0.5" | Classic picket | ~20 |
| 1" | Open | ~18 |
| 3.5" | Privacy gaps | ~13 |
Last updated: October 2026 · Spacing and rail counts reflect common residential fencing practice. Measure your exact run (including gates and corners) for a precise order.
Fence calculator FAQ
At 8 ft spacing: 100 ÷ 8 = 13 (rounded up) + 1 = 14 posts. Add 2 more if your fence has a gate or a corner that needs its own posts.
With 5.5-inch pickets and a 0.5-inch gap, each picket covers 6 inches of fence, so 100 ft × 12 ÷ 6 = 200 pickets.
For a privacy fence, set pickets flush (0 gap) or board-on-board so no light shows through. For a classic open picket look, use a 0.5–1 inch gap.
Yes, for most wood fences. Set posts in a concrete footing below the frost line, about one-third of the post length underground. Concrete adds stability and prevents leaning.
Add 5–10% extra for pickets and rails to cover cuts and waste, plus dedicated gate posts if you have a gate. It's cheaper than a second lumber delivery.