How Many Bricks Do I Need?
A brick calculator estimates how many bricks are required for a wall by comparing the net wall dimensions with the effective size of each brick, including the mortar joint, then adding the wastage allowance you select.
For a useful estimate, enter the actual wall length, height and thickness instead of relying on one universal “bricks per square foot” rate. Brick dimensions, mortar spacing, openings and wall thickness can all change the final quantity.
How to Use the Brick Calculator
- Choose Imperial or Metric units. Use feet/inches or metres/millimetres.
- Enter wall length, height and thickness. For wall area only, use our Wall Area Calculator.
- Select a brick size or choose Custom. Custom dimensions are useful when your supplier's bricks differ from the presets.
- Check the mortar joint. The default is about 10 mm (3/8 in), but you can change it.
- Add doors and windows. Each opening is deducted from the gross wall area.
- Set wastage and optional price per brick. The calculator shows base bricks, waste bricks, total order quantity, approximate mortar volume and optional brick cost.
Brick Calculation Formula
This calculator uses a volume-based estimate so wall thickness is included rather than treating every wall with the same surface-area ratio.
Gross Wall Area = Wall Length × Wall Height
Net Wall Area = Gross Wall Area − Openings
Net Wall Volume = Net Wall Area × Wall Thickness
Effective Brick Volume = (Brick Length + Mortar) × (Brick Width + Mortar) × (Brick Height + Mortar)
Total Bricks = (Net Wall Volume ÷ Effective Brick Volume) × (1 + Wastage ÷ 100)
The final purchase quantity is rounded up to a whole brick. Intermediate dimensions are not rounded before the calculation.
Worked Brick Calculation Examples
Example 1: Simple Wall
Suppose a wall is 20 ft long × 10 ft high. Its gross wall area is:
20 × 10 = 200 sq ft
The final quantity still depends on the selected wall thickness, brick dimensions and mortar joint. That is why the calculator asks for those values instead of applying one fixed bricks-per-square-foot rate to every project.
Example 2: Wall With a Door Opening
A 20 ft × 10 ft wall has a gross area of 200 sq ft. A 3 ft × 7 ft door occupies:
3 × 7 = 21 sq ft
The net brickwork area becomes:
200 − 21 = 179 sq ft
The calculator then applies the selected wall thickness, effective brick dimensions and wastage to the 179 sq ft net wall area.
Brick Size and Mortar Joint Reference
Brick dimensions vary by country and manufacturer, so the safest approach is to confirm the actual product dimensions before placing an order. The calculator includes common presets but also allows custom dimensions.
| Example Brick | Dimensions | Use in Calculator |
|---|---|---|
| Common 9-inch brick preset | 9 × 4.5 × 3 in | Imperial preset |
| Common UK-size reference | 215 × 102.5 × 65 mm | Metric preset |
| Your supplier's brick | Actual dimensions | Choose Custom |
Bricks per Square Foot and Square Metre
Fixed area ratios can be useful for a quick check, but they are not universal. A single-layer wall made with one brick size does not use the same number of bricks per unit area as a thicker wall or a wall made with different brick dimensions.
For project planning, use your actual wall thickness and brick size above. If you only know the wall's surface dimensions, first calculate the area and then return here with the correct wall thickness.
What Affects Your Brick Estimate?
- Wall thickness: a thicker masonry wall contains more brick volume than a thin partition of the same length and height.
- Brick dimensions: small differences between nominal and actual brick sizes accumulate across a large wall.
- Mortar joint: the joint changes the effective dimensions occupied by each brick.
- Doors and windows: openings reduce the net brickwork area and should be deducted.
- Bond pattern and cuts: corners, returns and complex patterns can increase cutting and waste.
- Handling and site conditions: breakage and difficult layouts may justify a higher wastage allowance.
After estimating bricks, use the Cement Calculator and Sand Calculator for related masonry materials. For structural concrete elements, use the Concrete Volume Calculator.
Common Brick Estimation Mistakes
- Ignoring openings: subtract doors and windows before calculating the final brickwork volume.
- Using the wrong wall thickness: half-brick and full-brick walls can require very different quantities.
- Assuming every brick has the same dimensions: confirm the actual supplier dimensions where possible.
- Ignoring mortar joints: mortar changes the effective space occupied by each brick.
- Ordering only the theoretical minimum: cuts, damage and breakage are why the calculator includes an adjustable wastage allowance.
How to Verify Your Brick Estimate
- Recheck wall length, height and thickness.
- Confirm the brick's actual dimensions with the supplier.
- Confirm the intended mortar-joint thickness.
- Check that doors and windows were entered correctly.
- Review the selected wastage percentage.
- Compare the final quantity with your mason, supplier or project professional before ordering.
How we calculate: Utilixea estimates brick quantity using the wall, brick, mortar, opening and wastage values you enter. The result is a planning estimate; brick tolerances, bond patterns, cuts, workmanship and site conditions can change the final material requirement.
Frequently Asked Questions
There is no single universal rate because brick face dimensions, mortar joints and wall construction vary. Use your actual brick dimensions and wall thickness in the calculator for a project-specific estimate.
The number depends on brick dimensions, mortar joint and wall construction. For a common 215 × 102.5 × 65 mm brick, roughly 60 bricks per square metre is a familiar guide for a single-layer face, but thicker walls require more. Use the calculator for your actual wall thickness.
Yes, a practical allowance helps cover cuts, breakage and damaged units. The calculator starts at 5%, but you can change the percentage to match your project and site conditions.
Yes. Add each opening to the calculator and its area will be deducted from the gross wall area before the brick quantity is calculated.
Yes. Mortar occupies space between bricks, so changing the joint thickness changes the effective brick dimensions used by the calculation.
Yes. Choose Custom under Brick Size and enter the actual length, width and height of the brick in inches or millimetres.
No construction estimate is perfectly exact. The result is intended for planning and depends on the values you enter. Brick tolerances, bond pattern, cuts, handling and workmanship may affect the final quantity, so verify the order with your supplier or project professional.
Plan the Rest of Your Wall Materials
Once your brick quantity is ready, continue with the Cement Calculator and Sand Calculator to estimate related mortar materials. For finishing work, the Plastering Calculator can help with the same wall surfaces.
