Fence Post & Concrete Calculator
Enter your fence length, post spacing and hole size to get the number of posts and bags of concrete to set them. Choose 4x4 or 6x6 posts and 40, 60 or 80 lb bags to match what you are buying.
Common questions
How is the post count figured?
Fence length divided by spacing, rounded up, plus one end post. Add one post for each corner and each side of a gate.
Why does post size change the concrete?
The post fills part of the hole. A 6x6 is actually 5.5 inches wide and a 4x4 is 3.5 inches, so a 6x6 needs less concrete in the same size hole.
Which bag size should I pick?
Choose 40, 60 or 80 lb to match what you are buying. Yields used are about 0.30, 0.45 and 0.60 cu ft per bag.
How deep and wide should holes be?
A common rule is a hole about 3 times the post width and at least 24 inches deep. Local frost depth and code can require more. Call 811 before digging.