🧱 Brick & Block Calculator
Enter your wall dimensions and pick a brick or block type, and get the number to buy — including the mortar joint and a waste allowance.
With waste
1,207
buy this many
Bare count
1,098
Wall area
160 ft²
Units per ft²
6.9
Units = wall area ÷ (brick face + mortar joint), rounded up, plus a waste allowance. A 3⁄8″ (10 mm) joint is standard. Subtract door and window openings from the wall area for a tighter estimate. 🔒 In your browser.
How the brick & block calculator works
A brick or block occupies its own face area plus one mortar joint on the width and height. The tool works out that effective face area, divides the wall area (length × height) by it to get the bare count, rounds up, and adds your waste percentage. Presets cover modular and standard bricks and standard concrete block (CMU); you can change the mortar joint and waste to match your job.
A 3⁄8 inch (10 mm) mortar joint is standard for both brick and block. Rules of thumb: about 7 modular bricks per square foot of wall, or roughly 1.125 concrete blocks per square foot. Subtract door and window openings from the wall area, and buy 5–10% extra for cuts and breakage.
Frequently asked questions
How many bricks do I need per square foot?
About 7 modular bricks per square foot of wall face, including the mortar joint. For a single-thickness wall, multiply the wall area in square feet by 7 for a quick estimate; this tool does it precisely for your brick size and joint.
How many concrete blocks per square foot?
A standard 16 × 8 inch block covers about 0.89 square feet with its mortar joint, so roughly 1.125 blocks per square foot of wall. For 100 square feet that is about 113 blocks before waste.
Does the mortar joint change the count?
Yes — the joint adds to each unit’s effective size, so a wall needs slightly fewer bricks than the bare brick size suggests. A 3⁄8 inch (10 mm) joint is standard and is included in this calculator.
How much waste should I add?
Typically 5–10% for cuts, breakage and future repairs. Add more for walls with lots of corners, openings or decorative cuts. Keeping a few spares from the same batch helps with later repairs.
Should I subtract windows and doors?
For a tighter estimate, yes — subtract the area of any openings from the wall area before calculating. For a rough buying figure you can leave them in, which builds in a little extra.