Concrete Block Calculator
Estimate concrete blocks for a wall from area, openings, modular dimensions, and waste.
Concrete blocks for a wall
The calculation uses the visible block face plus mortar joint to obtain modular area. Openings are subtracted before units are counted.
Blocks = net wall area ÷ modular block area
Use actual dimensions and waste
Blocks vary by system and market. Enter actual dimensions; waste covers cuts and breakage but does not replace course and corner layout.
Frequently asked questions
How many blocks fit per square foot?
It depends on visible dimensions and joint thickness; the calculator derives it from your inputs.
Does this work for CMU?
Yes. Enter the dimensions of the face occupying the wall.
Does it calculate mortar?
No. It estimates block quantity only.
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