How to use the Concrete Block Calculator

Estimate concrete masonry blocks needed for a wall with specified modular block size.

Calculation formula

Block count = ceil(wall length × wall height × 144 ÷ (nominal block length × nominal block height) × (1 + waste%)).

Recommended steps

1. Enter values using the units shown beside each field.
2. Review whether the example assumptions match your situation.
3. Run the calculator and compare the key metrics.
4. Use the source data or official rates when precision matters.

Known limitations

Uses nominal modular sizes with mortar; does not account for openings, reinforcing, lintels or structural design.