Brick Calculator
A standard US modular brick with a 3/8-inch mortar joint covers about 0.148 square feet — roughly 6.75 bricks per square foot. Enter your wall and get the count, plus mortar. Runs 100% in your browser.
Brick Calculator
About this brick calculator
Brick math starts from one rate: a standard US modular brick (3-5/8 × 7-5/8 in) with a 3/8-inch mortar joint occupies about 0.148 square feet, which inverts to 6.75 bricks per square foot for a single-wythe wall. Double-wythe (two bricks thick, structural) doubles it to 13.5. Multiply wall area by the rate, add waste for cuts and breakage, and you have the order. Our brick guide covers wythes, mortar, and the UK metric variant.
Mortar runs roughly one 70-lb bag per 140 bricks at standard joint thickness — thicker joints or sloppier laying drink more. And the batch rule matters more for brick than for almost any other material: bricks from different kiln runs can differ visibly in color, so order the full quantity (plus waste) from one batch, and keep spares for future repairs.
UK builders use a different standard: a 215 × 102.5 × 65 mm brick with 10 mm joints needs about 60 bricks per square metre for a single skin, 120 for double. If you are working in metric, convert your wall to square metres and use 60/120 instead — the waste rule (5–10%) is the same.
How to use
- Measure your wall length and height in feet.
- Choose single or double wythe (single is standard for garden and veneer walls).
- Pick a waste allowance — 10% covers cuts and breakage for most walls.
- Optionally enter the price per brick, then press Calculate.
Good to know
- US modular brick with 3/8-inch joints assumed; other brick sizes and joint widths change the per-square-foot rate — divide 144 by (brick length + joint) × (brick height + joint) for your brick.
- Does not subtract doors and windows — measure net wall area yourself for walls with large openings, or let the waste allowance absorb small ones.
- Structural brickwork (load-bearing, retaining, chimneys) needs engineering and code compliance — this is a quantity tool only.
Frequently asked questions
How many bricks do I need for a 20x6 wall?
A 20×6 ft single-wythe wall is 120 sq ft × 6.75 bricks per sq ft = 810 bricks exact — order 891 with a 10% waste allowance, plus 7 bags of mortar.
How many bricks per square foot?
About 6.75 standard US modular bricks per square foot with 3/8-inch mortar joints (published figures range 6.55–6.9 by exact brick and joint). Double-wythe walls need 13.5 per square foot.
How much mortar do I need per 100 bricks?
Roughly one 70-lb bag per 140 bricks, so about 0.7 bags per 100 bricks — or 7 bags per 1,000 bricks. Thicker joints use more.
What is the difference between single and double wythe?
Single wythe is one brick thick (veneer or garden walls); double wythe is two bricks thick (structural walls). Double wythe doubles both the brick count and the mortar.
How many bricks per square metre (UK)?
About 60 standard UK bricks per square metre for a single skin, 120 for double skin, before 5–10% waste. UK bricks are 215 × 102.5 × 65 mm with 10 mm joints.