What to measure
How to use the brick calculator
Enter the wall’s length and height, subtract any doors and windows in square feet, and choose the brick size. Keep 5% for breakage and cuts. The result is for a single-wythe (one brick thick) wall.
The formula
- Bricks per sq ft = 144 ÷ ((brick length + ⅜) × (brick height + ⅜)), dimensions in inches
- Bricks = wall area × bricks per sq ft × (1 + extra %)
- Mortar ≈ 7 bags of masonry cement + 1 ton of sand per 1,000 bricks
Worked example: 20 × 8 ft wall, modular brick
- Bricks per sq ft: 144 ÷ (8 × 2.625) = 6.86
- 160 sq ft × 6.86 × 1.05 = 1,152 bricks
- Mortar: 9 bags of masonry cement and about 1.15 tons of sand
Brick sizes
| Brick | Size (in) | Per sq ft |
|---|---|---|
| Modular | 7⅝ × 2¼ | 6.86 |
| Standard | 8 × 2¼ | 6.55 |
| Queen | 7⅝ × 2¾ | 5.76 |
| King | 9⅝ × 2⅝ | 4.80 |
Bricks and mortar by wall area
Modular brick, 3/8 in joints, 5% extra.
| Wall area | Bricks | Masonry cement | Sand |
|---|---|---|---|
| 50 sq ft | 360 | 3 bags | 0.36 tons |
| 100 sq ft | 720 | 6 bags | 0.72 tons |
| 200 sq ft | 1,440 | 11 bags | 1.44 tons |
| 300 sq ft | 2,160 | 16 bags | 2.16 tons |
| 500 sq ft | 3,600 | 26 bags | 3.6 tons |
| 1,000 sq ft | 7,200 | 51 bags | 7.2 tons |
Common mistakes
- Leaving out the mortar joint. Bricks per square foot depends on the brick plus its 3/8 in joint. Using the bare brick size overcounts.
- Assuming all bricks are the same size. Modular, queen and king bricks have different face sizes, so the count changes with the brick. Check the size on the pallet.
- Forgetting the openings. Subtract doors and windows, but only once if you also measured the wall around them.
- Cutting the waste allowance. Corners, openings and broken bricks use more than you expect, and a later batch may not match in color.
Frequently asked questions
How many bricks are in a square foot?
About 6.86 modular bricks per square foot of wall with 3/8 in mortar joints. Queen bricks need about 5.76 and king bricks about 4.8.
How many bricks do I need for a 20 x 8 ft wall?
160 sq ft × 6.86 = 1,097 modular bricks, or 1,152 with 5% extra.
How much mortar for 1,000 bricks?
About 7 bags of masonry cement and 1 ton of masonry sand for a single-wythe wall with 3/8 in joints.
Should I subtract windows and doors?
Yes, for brick. Enter the total area of the openings in square feet. A standard door is about 21 sq ft.
How many bricks do I need for 100 square feet?
720 modular bricks with 5% extra. Queen bricks take 605 and king bricks 504 for the same wall.
How do I count bricks for a wall with a door and a window?
Add up the openings and enter them in square feet. A 30 × 8 ft wall with a 21 sq ft door and a 15 sq ft window leaves 204 sq ft, or 1,469 modular bricks with 5% extra.
Does the count work for a double brick wall?
The calculator is for one wythe, one brick thick. For a wall two bricks thick, double the bricks and the mortar.
Sources
Formulas and defaults last reviewed October 30, 2026. How we check our math.