Fence materials calculator
For a straight wood picket or privacy fence. Set post spacing, rails per section and hole size to match your design; the concrete figure subtracts the post from the hole.
Materials takeoff
Fence Materials Calculator · https://estimahome.com/fence-calculator/
Fence length: 100 ftFence height: 6 ft
- Sections
- 13
- Min. post length
- 8 ft
- Concrete per hole
- 0.92 cu ft
- Total concrete
- 12.89 cu ft
| No. | Item | Qty | Unit | Unit cost | Amount |
|---|---|---|---|---|---|
| 1 | Posts, 8 ft (min. 8 ft) | 14 | ea | $16.00 | $224.00 |
| 2 | Rails, 8 ft | 39 | ea | $6.00 | $234.00 |
| 3 | Pickets, 6 ft | 230 | ea | $3.50 | $805.00 |
| 4 | Concrete, 80 lb bags | 22 | bag | $6.50 | $143.00 |
- Subtotal
- $1,406.00
- Likely range
- $1,195.10 – $1,616.90
- Straight run, no gates. Add a post for each extra corner or end and two for each gate.
- Not included: nails or screws, gate hardware, post caps.
Buy these materials
- 14 fence posts (8 ft)Amazon search for fence posts (8 ft) (opens in new tab)
- 39 rails (8 ft)Amazon search for rails (8 ft) (opens in new tab)
- 230 pickets (6 ft)Amazon search for pickets (6 ft) (opens in new tab)
- 22 80 lb bags of concreteAmazon search for 80 lb bags of concrete (opens in new tab)
Links open a store search for each item. Check sizes and grades against your plan.
Quick reference
- A straight 100 ft fence with posts 8 ft apart needs 14 posts: one per section plus one to finish the run.
- 100 ft of 5.5 in pickets with no gap is 219 pickets before waste.
- A 10 × 24 in hole around a 4×4 post holds about 0.92 cu ft of concrete.
How it's calculated
⌈x⌉ means round up to the next whole unit; ⌊x⌋ means round down. Every quantity you buy is rounded up.
Sections = ⌈ fence length ÷ post spacing ⌉Posts = sections + 1Rails = sections × rails per sectionPickets = ⌈ length × 12 ÷ (picket width + gap) × (1 + waste ÷ 100) ⌉Concrete per hole (cu ft) = π × (hole dia ÷ 24)² × (depth ÷ 12) − (post width ÷ 12)² × (depth ÷ 12)Bags = ⌈ posts × concrete per hole ÷ bag yield ⌉Minimum post length = fence height + hole depth ÷ 12Cost = Σ (quantity × unit price); range = cost × (1 ± range % ÷ 100)
Worked example
A 100 ft run with posts every 8 ft is 13 sections and 14 posts. At 3 rails per section that is 39 rails. 5.5 in pickets set tight with 5% waste come to 230. A 10 in hole 24 in deep around a 3.5 in post takes 0.92 cu ft of concrete; 14 holes is 12.89 cu ft, or 22 bags of 80 lb mix. Set 24 in deep, a 6 ft fence needs posts at least 8 ft long. Materials at the default prices: $1,406.00.
Questions
How many fence posts do I need?
Fence length ÷ post spacing, rounded up, plus one. Add a post at every extra corner or end, and plan two heavier posts for each gate.
How deep should fence posts be set?
A common rule is one third of the post's height above ground, and below the frost line in cold climates. For a 6 ft fence that is about 24 in.
How many bags of concrete per fence post?
For a 10 in hole 24 in deep around a 4×4, about 0.9 cu ft, which is one and a half 80 lb bags. Bigger holes or deeper posts take more.
Cite: “Fence Materials Calculator.” EstimaHome, https://estimahome.com/fence-calculator/. Updated 2026-10-20. Formulas in machine-readable form: /api/calculators.json.