Fence Post Calculator — Estimate Posts & Concrete Instantly
Calculate number of fence posts, concrete bags, post hole volume, gravel base, and post caps. Includes corner, gate, and end post calculations for any terrain.
2
Post Sizes
2
Concrete Types
3
Terrains
100%
Free to Use
Enter Post Details
Your Results
Ready to Calculate
Enter your fence post details and click Calculate to see estimates.
Total Posts Needed
0 posts
Concrete Bags
0 bags
Post Hole Volume
0 cu ft
Gravel Base
0 cu ft
Post Caps
0 caps
Corner Posts
0 posts
Gate Posts
0 posts
End Posts
0 posts
Estimated Cost
—
Calculation Summary
Post Size4x4
Hole Depth24 in
TerrainFlat
Post Spacing8 ft
Material Cost—
Frequently Asked Questions
A general rule is to bury one-third to one-half of the post height. For a 6 ft fence, dig holes 24–30 inches deep. In cold climates, holes must extend below the frost line to prevent frost heave.
For a standard 4x4 post with a 24-inch deep hole, you will need approximately 1.5 bags of 50 lb concrete mix. Fast-setting concrete sets in 20–40 minutes, while traditional mix requires 24–48 hours to cure.
Yes, 4–6 inches of gravel at the bottom of each post hole improves drainage and helps prevent wood rot. It also provides a stable base for the post and reduces frost heave in cold climates.
Corner posts bear more load and should be larger (6x6 recommended) or set deeper than line posts. Gate posts also need extra support due to the weight of the gate. End posts terminate the fence run and require additional bracing.