Estimate the concrete needed to set deck posts.
The concrete around a post is the difference between the round hole volume and the post's own volume. Multiplying by the number of posts gives the total pour. Concrete secures each post against movement, so estimating the fill volume per post tells you how many bags to buy.
Deck Post Concrete
Concrete/post = hole volume - post volume
Concrete/post = hole volume - post volume The concrete around a post is the difference between the round hole volume and the post's own volume. Multiplying by the number of posts gives the total pour.
Concrete secures each post against movement, so estimating the fill volume per post tells you how many bags to buy.
This calculator takes 4 inputs: Number of posts, Hole diameter, Hole depth, Post width. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.