Brick walls are planned on a grid. Each brick plus its mortar joint takes up a fixed rectangle of wall, so the count depends only on the wall area and the brick size. This calculator finds the net wall area, divides it by the space one brick occupies, multiplies by the number of wythes and adds a waste allowance. It also estimates premixed mortar bags and, for single-wythe veneer, the wall ties the building code requires.
How to use the brick calculator
- Choose US or Metric units.
- Enter the wall’s length and height, or a known area.
- Subtract openings such as doors and windows if there are any.
- Pick the brick size, or choose Custom and enter the brick’s length, height, depth and joint.
- Choose single or double wythe.
- Set the extra bricks, the bricks per bag rating on your mortar and the extra mortar allowance.
Brick formulas
Bag ratings assume standard modular brick. When you choose a larger brick, the calculator scales the rating by how much more joint volume each brick has.
Worked example: a 20 × 8 ft veneer wall
Area: 20 × 8 = 160 ft². Modular brick: 144 ÷ (8 × 2⅔) = 6.75 per ft².
Bricks: 160 × 6.75 = 1,080; with 5% extra → 1,134 bricks.
Mortar: 1,080 ÷ 37 × 1.1 = 32.1 → 33 bags of 80-lb premix.
The wall is 36 courses tall, and as veneer it needs 160 ÷ 2.67 = 60 wall ties.
Built with utility brick instead, the same wall needs only 3 bricks per square foot — 504 with waste — and goes up much faster, though each brick is heavier.
Bricks per square foot by size
| Brick (actual size, in) | Module with ⅜ in joint | Bricks per ft² |
|---|---|---|
| Modular, 7⅝ × 2¼ | 8 × 2⅔ | 6.75 |
| Engineer modular, 7⅝ × 2¾ | 8 × 3.2 | 5.63 |
| Closure modular, 7⅝ × 3⅝ | 8 × 4 | 4.50 |
| Roman, 11⅝ × 1⅝ | 12 × 2 | 6.00 |
| Norman, 11⅝ × 2¼ | 12 × 2⅔ | 4.50 |
| Utility, 11⅝ × 3⅝ | 12 × 4 | 3.00 |
These are the modular coursing figures published by the Brick Industry Association. Non-modular and imported brick vary, so measure a sample and use the custom option.
Mortar and ties
Premixed mortar in 80-lb bags is convenient for small walls, steps and repairs. Type N is the usual choice for above-grade veneer and garden walls; Type S is stronger and used below grade and in retaining or load-bearing work. Bag ratings leave nothing for waste — mortar dropped from the trowel and joints that are filled fuller than ⅜ inch — so a 10–25% allowance is sensible, especially for a first project.
Brick veneer over wood framing must be anchored to the structure. The International Residential Code (R703.8.4) limits each tie to supporting no more than 2.67 ft² of wall, with ties no more than 32 inches apart horizontally and 24 inches vertically. Veneer also needs flashing and weep holes at the base and above openings so water that gets behind the brick can escape.
Buying tips
- Brick is sold by the piece or by the cube or pallet, often around 500 modular bricks; ask how your supplier packages it.
- Buy everything from the same production run and blend bricks from several pallets as you lay them.
- Keep a few dozen spares for repairs.
For walls built from concrete masonry units, use the concrete block calculator. If you will mix mortar on site, the sand calculator converts the sand volume into tons.
Frequently asked questions
How many bricks are in a square foot?
Standard modular brick (7⅝ × 2¼ in face) laid with ⅜-inch joints take 6.75 bricks per square foot of wall, because each brick plus joint occupies 8 × 2⅔ inches. Larger units take fewer: Norman brick 4.5 per ft² and utility brick 3 per ft².
How many bricks do I need for a 100 square foot wall?
A single-wythe wall of modular brick needs 100 × 6.75 = 675 bricks. With 5% extra for breakage and cuts, order about 709. A double-wythe wall needs twice as many.
How much mortar do I need for 1,000 bricks?
An 80-lb bag of premixed mortar is typically rated to lay about 35–40 standard bricks, so 1,000 bricks need roughly 27 bags before waste and about 30 with a 10% allowance. For large jobs, mixing masonry cement and sand on site is cheaper.
What is a wythe?
A wythe is a single vertical layer of masonry one unit thick. Brick veneer on a house is one wythe tied back to the framing; a freestanding garden wall is often two wythes joined with metal ties or header bricks.
What size is a standard brick in the US?
The most common US brick is the modular brick, about 3⅝ inches deep, 2¼ inches high and 7⅝ inches long. It is sized so that the brick plus a ⅜-inch mortar joint fits a 4-inch building module, with three courses rising 8 inches.