Estimate blocks and mortar for your masonry project in seconds
Use this block and mortar calculator to quickly estimate how many concrete blocks and mortar bags you need for walls, foundations, and masonry projects.
Enter the wall length and height in feet. The calculator determines total wall area, divides by the block face area, and calculates how many blocks are required. Mortar bags are estimated based on blocks per 100.
A 40 ft by 8 ft wall:
How many blocks do I need?
Divide wall area by block area.
Mortar per block?
~10–12 bags per 100 blocks.
Should I order extra blocks?
Yes, add 5–10% extra for cuts and breakage.