Calculators › Fence calculator

Fence calculator

Fence length in, a material list out: posts (with corners and gates), rails, pickets or panels, and bags of concrete for the post holes.

How it works

Worked example

100 ft of 6 ft privacy fence with 8 ft spacing, two corners and one gate needs 17 posts, 39 rails and 219 pickets (1×6). Each 10.5 in hole is 30 in deep (24 in of concrete over 6 in of gravel), about 47 × 50 lb bags of fast-setting concrete in total.

Tips before you buy

Call 811 before you dig so buried utilities get marked. Free in the US. Post depth rules vary: in cold climates footings must go below the frost line, and many HOAs and cities limit fence height or require a permit. Check before buying.

Common questions

How many fence posts do I need for 100 feet?

With 8 ft spacing, 13 sections need 14 posts, plus one for each extra corner and gate.

How deep should fence posts be?

A common rule is one-third of the fence height above ground, plus about 6 in of gravel, so roughly 2 ft of concrete for a 6 ft fence. Go below your frost line where required.

How many bags of concrete per fence post?

For a 4×4 post in a 10–11 in hole about 2 ft deep, roughly 2–3 × 50 lb bags of fast-setting concrete.

More project calculators

Estimates for planning only. Product coverage and yields vary, so check the label. Last checked 2026-10-22.