Estimate the number of concrete blocks and mortar bags for a wall.
What this calculator does
For a standard 16×8-inch block, about 1.125 blocks cover each square foot of wall. Enter the wall length and height and this calculator estimates the blocks needed (with waste) and the mortar bags.
It’s a planning estimate — confirm with your supplier.
The default scenario, worked through
On the values this calculator opens with, the blocks needed is 189. Underneath, Wall area comes out at 160 ft² and Mortar bags at 6. Change any field and every figure updates as you type.
Getting your answer
- Enter the wall length and height in feet.
- Read the block count including waste.
- Check the estimated mortar bags.
The formula
wall area = length × height
blocks = area × 1.125 × (1 + waste)
FAQ
How many blocks per square foot?
About 1.125 standard 16×8-inch blocks per square foot of wall.
How much mortar do I need?
Roughly one bag per 33 blocks, though it varies with joint size and technique.
Should I add waste?
Yes — about 5% covers breakage and cuts, which this estimate includes.