How this calculator works
Each brick plus its share of mortar covers (length + joint) × (height + joint) square inches of wall. Dividing 144 sq in by that number gives bricks per square foot, which is multiplied by the net wall area.
Bricks per sq ft = 144 ÷ ((Brick length + Joint) × (Brick height + Joint))
Bricks = round up( Net area × Bricks per sq ft × (1 + Waste%/100) )
Assumptions and tips
- Single wythe (one brick thick). Double the count for a two-wythe wall.
- Running bond; special patterns and soldier courses change waste.
Worked example
Using the default values in the calculator above:
| Input | Value |
|---|---|
| Wall length | 20 ft |
| Wall height | 8 ft |
| Openings to subtract | 0 sq ft |
| Brick length | 7.625 in |
| Brick height | 2.25 in |
| Mortar joint | 0.375 in |
| Waste allowance | 5 % |
| Result | Value |
|---|---|
| Bricks needed | 1,152 bricks |
| Bricks per sq ft | 6.86 |
| Net wall area | 160 sq ft |
Step by step:
- One brick + joint = (7.625 + 0.375) × (2.25 + 0.375) = 21 sq in
- Bricks per sq ft = 144 ÷ that = 6.857
- Bricks = 160 sq ft × 6.857 × 1.05 → 1152
Bricks per square foot by brick size
3/8 in mortar joint, 100 sq ft wall, 5% waste.
| Brick (L × H) | Bricks per sq ft | Bricks per 100 sq ft |
|---|---|---|
| Modular 7 5/8 × 2 1/4 in | 6.86 | 720 bricks |
| Queen 7 5/8 × 2 3/4 in | 5.76 | 605 bricks |
| King 9 5/8 × 2 5/8 in | 4.8 | 504 bricks |
| Utility 11 5/8 × 3 5/8 in | 3 | 315 bricks |
Common mistakes to avoid
- Forgetting that a double-wythe wall needs twice the bricks.
- Not ordering enough from one batch — colors vary between production runs.
Frequently asked questions
How many modular bricks per square foot?
With a 3/8 in joint, a US modular brick (7 5/8 × 2 1/4 in) gives about 6.86 bricks per square foot (144 ÷ (8 × 2.625)).
How much waste should I allow for bricks?
About 5% for simple walls; more for many cuts, corners or openings.