Fence post calculator
How many fence posts do you need?
Enter your fence run and post spacing to get a post count, concrete bags, and an estimated cost.
Enter your fence line
National average is $15–$40 per linear ft installed — material-only estimates will run lower.
Results
- Posts needed
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- Concrete (2 bags/post)
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- Panels needed
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- Estimated cost
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Posts assume one extra post beyond each spacing gap — the run always starts and ends on a post.
Estimates only — corner, end and gate posts may need different sizing or spacing than a straight run.
How it's calculated
Run ÷ spacing, plus one.
A fence run is divided into equal gaps by its spacing, rounded up to a whole number of gaps, then one more post is added — since a straight run has one more post than it has gaps between them. Concrete is then a fixed number of bags per post.
FAQ
Common questions
How many posts do I need for my fence?
Divide your fence run by the post spacing and round up, then add one — a run always starts and ends on a post. At the default 8 ft spacing, a 150 ft run needs 20 posts. Enter your own run and spacing above for an exact count.
How much concrete per post?
We default to 2 bags of 60 lb concrete mix per post, enough for a typical residential post hole. Deeper holes, larger posts, or corner/gate posts that carry more load may need more.
How deep should fence post holes be?
A common rule of thumb is one-third to one-half of the post's above-ground height, and below your local frost line in climates that freeze. Check your local code for exact requirements.
Do corner and gate posts need different spacing?
Corner, end and gate posts are typically set independently of the regular spacing interval — they mark the start/end of a run or the width of an opening rather than an evenly spaced line post.