Posts and panels by spacing, concrete bags per post,
and a printable materials list for a 100-foot fence.
Quick answer
A 100-foot fence at 8 ft spacing
needs 14 posts and
13 panels.
At 6 ft spacing you need 18 posts and 17 panels.
Add 1 extra post for each gate and each corner turn.
Calculate Your Exact Materials
- 14 fence posts
- 13 fence panels (8 ft wide)
- 26 fence rails (2 per section)
- 28 bags of 80 lb concrete — planning estimate
- Add 1 post per gate and 1 post per corner turn
Fence Posts Needed for 100 Feet by Post Spacing
Post spacing changes the total count significantly.
Eight feet is standard for prefab panel fencing.
Six feet is better for tall or wind-exposed fences.
| Post Spacing | Sections | Posts | Rails (2/section) | Concrete Bags |
|---|---|---|---|---|
| 4 ft spacing | 25 | 26 posts | 50 rails | 52 bags |
| 6 ft spacing | 17 | 18 posts | 34 rails | 36 bags |
| 8 ft spacing ← standard | 13 | 14 posts | 26 rails | 28 bags |
| 10 ft spacing | 10 | 11 posts | 20 rails | 22 bags |
How Post Count Works
Sections = fence length ÷ post spacing (round up)
Posts = sections + 1
The +1 accounts for the post at both ends of the run.
A 100-foot fence at 8 ft spacing has 12.5 sections — round up
to 13 — then add 1 end post to get 14 posts total.
Adding Gates and Corner Turns
Each gate adds 1 extra post on the latch side.
Each corner or direction change adds 1 extra post at the turn point.
- Straight 100 ft fence, no gates or corners: 14 posts
- Same fence with 1 gate: 15 posts
- Same fence with 1 gate and 2 corners: 17 posts
For gates and corners use the
Fence Calculator —
it adds extra posts automatically.
Posts Needed for Different Fence Lengths at 8 Ft Spacing
| Fence Length | Posts | Panels | Concrete Bags |
|---|---|---|---|
| 50 ft | 8 posts | 7 panels | 16 bags |
| 75 ft | 11 posts | 10 panels | 22 bags |
| 100 ft | 14 posts | 13 panels | 28 bags |
| 150 ft | 20 posts | 19 panels | 40 bags |
| 200 ft | 26 posts | 25 panels | 52 bags |
How Much Concrete Do You Need for Fence Posts?
A rough planning estimate is 2 bags of 80 lb concrete per post.
Actual concrete depends on your hole diameter and depth.
Concrete Calculator
— select the Fence Post Holes tab and enter your hole
diameter and depth.
A standard 10-inch diameter hole at 3 feet deep uses about
3 bags of 80 lb concrete. A smaller 8-inch hole at 2.5 feet
deep uses about 2 bags. Always check local frost line
depth requirements before digging.
Frequently Asked Questions
How many fence posts do I need for a 100-foot fence?
At 8 ft post spacing — the standard for prefab panel fencing —
a 100-foot fence needs 14 posts and 13 panels.
At 6 ft spacing you need 18 posts and 17 panels.
Add 1 post for each gate and 1 post for each corner turn.
How do I calculate fence post spacing?
Divide your total fence length by your chosen spacing.
Round up to the nearest whole number to get sections.
Add 1 to get total posts. For 100 feet at 8 ft spacing:
100 / 8 = 12.5 — round up to 13 sections — 14 posts.
What is the standard distance between fence posts?
Eight feet is the most common spacing for residential
panel fencing because it matches standard 8-foot prefab
panel widths. Six feet is better for taller fences,
wood privacy fences in windy areas, or anywhere extra
strength is needed.
How many bags of concrete do I need for fence post holes?
Use 2 bags of 80 lb concrete per post as a planning estimate.
Actual amounts depend on hole diameter and depth.
Use the Concrete Calculator
for exact bag counts based on your specific hole dimensions.
How deep should fence posts be set?
A common guideline is one third of the post length in the
ground. For a 6-foot above-ground fence, use 8-foot posts set
2 feet deep minimum — deeper in cold climates where frost
heave is a concern. Always check local building codes for
minimum depth requirements in your area.
Related Calculators
- Fence Calculator —
posts, panels, rails, and concrete for any fence length
with gates and corner posts - Concrete Calculator —
exact bags for fence post holes by diameter and depth - Mulch Calculator —
bags needed for garden beds and landscaping areas