Tool · Investor Sam Build

Brick and Block Calculator

June 30, 2026 • By the Investor Sam Editorial Team • Reviewed by Berly Sam Varghese, Editor
Bricks and blocks are counted by the wall face they cover, and the count per square foot depends entirely on the unit size and mortar joint. This calculator takes the wall area, the units that fill a square foot for your chosen brick or block, and a waste allowance for breakage and cuts, then returns the unit count and cost. Units needed is the padded wall area times the units per square foot.

Example: Wall face area: 200 sq ft · Units per square foot: 6.86 units · Waste allowance: 10 % · Price per unit: 0.65 $

Units needed1,510
Total unit cost$982
Area including waste220

Worked example

A 200 square foot brick wall using standard modular brick, which lays about 6.86 bricks per square foot with a 3/8-inch mortar joint, needs 200 x 6.86 = 1,372 bricks before waste. Adding 10% for breakage and cuts gives about 1,510 bricks. At $0.65 each that is roughly $981 in brick. For 8x8x16 block instead, you would enter about 1.125 units per square foot.

Frequently asked questions

How many bricks are in a square foot?

A standard modular brick with a 3/8-inch mortar joint covers about 6.86 bricks per square foot of wall face. Other brick sizes differ, and a standard 8x8x16 concrete block covers about 1.125 blocks per square foot. Set the units-per-square-foot input to match your specific unit.

Why is the waste allowance important for masonry?

Bricks and blocks break in transit and during cutting at corners, openings, and course ends, and you cannot always reuse a broken piece. A 5 to 10% allowance keeps you from stopping the job one course short, which is especially costly if the color or lot changes.

Does this include the mortar?

No, this counts the masonry units only. Mortar is estimated separately, roughly by the number of bags of mortar mix per hundred units or per so many square feet of wall. Add mortar, sand, and any ties or reinforcement to your material list on top of this count.

Should I account for the wall being a cavity or veneer?

This tool counts the visible face units. A single-wythe veneer uses one face; a double-wythe or cavity wall has two faces of masonry, so calculate each wythe separately and add them. Confirm the wall assembly before ordering so you do not buy half of what you need.

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Sources

Berly Sam Varghese · Editor, Investor Sam

Berly Sam Varghese is an engineer who treats money the way he treats any hard problem — something to be engineered, not gambled on. He funded years of education and built real financial stability the patient way, by living below his means and investing rather than borrowing. He writes for the person staring at a number they don’t yet know how to reach. He reviews and approves every article on Investor Sam and checks the figures against primary sources before anything is published. More about our standards.