How to use the brick calculator
- Enter the wall length and height in feet.
- Select your brick size from the dropdown menu.
- Set a waste percentage (5% is typical for straight walls, 10% or more for complex patterns).
- Read the estimated total bricks and mortar bags below.
How the brick calculator works
This brick calculator estimates materials for a single-wythe (one brick thick) wall. It multiplies the wall dimensions in feet by the industry-standard number of bricks per square foot for each brick type, then rounds up to the nearest whole brick.
The formula is straightforward: Bricks = ceil(Length (ft) x Height (ft) x Bricks per sq ft). The bricks-per-square-foot rate already includes the standard 3/8-inch mortar joint on all sides.
For example, a 10-foot by 8-foot wall using Modular bricks (which require 6.92 bricks per square foot):
- Wall area = 10 x 8 = 80 square feet.
- Base bricks = 80 x 6.92 = 553.6, rounded up to 554.
- With 5% waste: 554 x 1.05 = 581.7, rounded up to 582 bricks.
Standard brick sizes reference
Different regions and projects use different brick dimensions. The table below lists the nominal face dimensions used in this tool. All calculations assume a 3/8-inch mortar joint.
| Name | Length (inches) | Height (inches) | Bricks per sq ft |
|---|---|---|---|
| Modular | 7.625 | 2.25 | 6.92 |
| Standard | 8.0 | 2.25 | 6.72 |
| King | 9.625 | 2.75 | 4.73 |
| Queen | 7.625 | 2.75 | 5.88 |
Modular bricks are the most common choice for residential construction in the United States. King and Queen bricks cover more area per unit, which can speed up laying time on large commercial facades.
Estimating mortar bags
Beyond counting bricks, estimating mortar is essential for ordering supplies. A standard 80-pound bag of Type N or Type S mortar mix yields approximately 0.7 cubic feet of mixed mortar.
For a single-wythe wall, a practical rule of thumb is that one 80-pound bag lays about 35 to 40 Modular bricks. This brick calculator uses a conservative estimate of 35 bricks per bag to ensure you do not run short mid-project. If you are using larger King or Queen bricks, fewer bags are required because there are fewer joints per square foot.
Mortar volume depends heavily on joint thickness. If your project specifies a half-inch joint instead of the standard 3/8-inch joint, you will need roughly 30% more mortar than the estimate provided here.
Why waste percentage matters
No masonry project uses every brick perfectly. Bricks break during transport, get cut to fit corners and openings, or are discarded due to color variations. The waste percentage accounts for these inevitable losses.
- Straight runs: 3% to 5% waste is usually sufficient for simple, unbroken walls.
- Walls with openings: Windows and doors require cutting bricks, pushing waste to 7% or 10%.
- Complex patterns: Herringbone, basket weave, or circular designs generate significant offcuts. Plan for 10% to 15% waste.
Ordering too few bricks means paying for expedited shipping or risking a mismatched batch later. Ordering slightly more is always cheaper than a second delivery.
Common mistakes when estimating bricks
Even experienced builders make errors when calculating materials. Here are pitfalls to avoid:
- Forgetting mortar joints: Calculating based on bare brick dimensions overestimates how many bricks fit. Always include the 3/8-inch joint in both length and height.
- Ignoring wall thickness: This tool calculates for a single-wythe wall. A double-wythe (solid) wall requires exactly twice as many bricks.
- Mixing units: Ensure all inputs are in feet before converting. Mixing meters and feet without conversion leads to massive errors.
- Not subtracting openings: If your wall has a large garage door or windows, calculate the gross wall area first, then subtract the area of the openings before applying the waste factor.
If you need help converting land areas before planning a perimeter wall, an acres to square feet converter can establish your boundary lengths accurately.
Worked examples
Each result below was produced by the same code the tool runs, so you can check your own numbers against them.
| Example | Input | Result |
|---|---|---|
| Small garden wall | Wall length (feet): 6; Wall height (feet): 3; Brick size: modular; Waste percentage: 5 | Wall area: 18 sq ft; Bricks needed: 132; Bricks without waste: 125; Mortar (80 lb bags): 4 |
| House exterior wall | Wall length (feet): 20; Wall height (feet): 10; Brick size: standard; Waste percentage: 7 | Wall area: 200 sq ft; Bricks needed: 1,439; Bricks without waste: 1,344; Mortar (80 lb bags): 42 |
| Fence with King bricks | Wall length (feet): 30; Wall height (feet): 6; Brick size: king; Waste percentage: 10 | Wall area: 180 sq ft; Bricks needed: 938; Bricks without waste: 852; Mortar (80 lb bags): 27 |
FAQ
How many bricks are in a square foot?
For standard Modular bricks with a 3/8-inch mortar joint, you need approximately 6.92 bricks per square foot. Standard bricks require about 6.72 per square foot.
Does this brick calculator account for mortar joints?
Yes. The bricks-per-square-foot rates used in this tool already include a standard 3/8-inch (0.375 inch) mortar joint on all sides of the selected brick size.
How many bricks does an 80-pound bag of mortar lay?
As a general rule, one 80-pound bag of mortar mix lays approximately 35 to 40 Modular bricks in a single-wythe wall with 3/8-inch joints.
What waste percentage should I use?
Use 5% for a straight wall with no cuts. Increase to 7% or 10% if the wall includes windows, doors, or corners that require cutting bricks.
Can I use this for a double-thick wall?
This tool calculates for a single-wythe (one brick thick) wall. For a double-wythe solid wall, multiply the final brick count by two.
Is my data sent to a server?
No. This brick calculator runs entirely in your browser. Your wall dimensions and results are never uploaded or stored anywhere.