How to use this calculator
Start by entering the total length of your fence line in feet. Select the fence type and post spacing that match your project, then add any corners and gates. The calculator instantly shows the total number of posts, recommended hole depth, concrete needed, and a complete materials shopping list.
Corner posts and gate posts are calculated separately because they require heavier construction. Each corner adds one extra post, and each gate adds two posts (one on each side of the opening).
Post spacing by fence type
Privacy and picket fences perform best with posts every 6 to 8 feet. Taller privacy fences and those in windy areas benefit from the tighter 6 foot spacing to prevent panels from flexing or leaning over time.
Split rail fences typically use 8 to 10 foot spacing because the rails themselves provide lateral strength. The rails slot directly into holes drilled through the posts, creating a self bracing structure.
Chain link and farm fences can handle wider spacing (up to 10 feet) because the mesh or wire provides continuous tension between posts. Terminal posts at ends, corners, and gates should always be set in concrete regardless of line post treatment.
Post hole depth and concrete
The general rule is to bury one third of the total post length, plus an additional 6 inches for a gravel drainage base at the bottom of the hole. This gravel layer is critical because it prevents water from pooling against the post bottom, which is the number one cause of premature post rot.
Fast setting concrete is the preferred choice for fence posts. You can pour it dry into the hole around the post, add water, and it sets in about 20 to 40 minutes. This lets you move on to the next post quickly without waiting hours for standard concrete to cure.
Frequently asked questions
What is the standard spacing between fence posts?
Most residential wood fences use 8 foot spacing, though 6 foot spacing is better for tall fences and high wind areas. Chain link and farm fences can go up to 10 feet between posts because the mesh or wire adds structural support.
How deep should fence post holes be?
Bury one third of the total post length plus 6 inches for gravel drainage, with a minimum of 24 inches. In cold climates, the bottom of the post footing should reach below the local frost line to prevent the post from heaving upward during freeze and thaw cycles.
How much concrete do I need per fence post?
Plan on one to two 50 pound bags of fast setting concrete per post, depending on hole depth and post size. Larger 6x6 posts and deeper holes need more concrete. Corner and gate posts should always get the full concrete treatment even if you skip concrete on some line posts.
Should I use wood or metal fence posts?
Wood 4x4 posts are ideal for privacy and picket fences because they accept screws and nails easily. Metal T posts are the go to choice for farm wire fencing because they resist rot and cost less per post. Steel pipe posts are strongest and work well for chain link, but they cost more and require special hardware to attach rails and panels.