Quick answer
Bricks per square foot = 144 ÷ ((brick length + joint) × (brick height + joint)). A 20 × 8 ft wall (160 ft²) with 7.625 × 2.25 inch bricks and 3/8 inch joints needs 1,152 bricks with waste and about 8.85 ft³ of mortar.
Enter the wall size, brick size, joint and waste allowance. The calculator returns the brick count, net area and mortar.
Related tools: Concrete Block Calculator: Concrete blocks and mortar volume for a wall. Roof Pitch Calculator: Roof pitch as rise per 12 inches, angle, slope percent and rafter length factor. Tile Calculator: Number of tiles (and boxes) for an area.
How to use the Brick Calculator
- Enter wall length (ft) (above 0).
- Enter wall height (ft) (above 0).
- Optionally, enter openings (optional) (ft²) (0 or more).
- Enter brick length (in) (above 0). It starts at 7.625.
- Enter brick height (in) (above 0). It starts at 2.25.
- Enter brick depth (wall thickness) (in) (above 0). It starts at 3.625.
- Enter mortar joint (in) (0 or more). It starts at 0.375.
- Enter waste allowance (%) (between 0 and 100). It starts at 5.
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Wall length | A number, in ft | > 0 |
| Wall height | A number, in ft | > 0 |
| Openings (optional) (optional) | A number, in ft² | ≥ 0 |
| Brick length | A number, in in | > 0, starts at 7.625 |
| Brick height | A number, in in | > 0, starts at 2.25 |
| Brick depth (wall thickness) | A number, in in | > 0, starts at 3.625 |
| Mortar joint | A number, in in | ≥ 0, starts at 0.375 |
| Waste allowance | A number, in % | ≥ 0, ≤ 100, starts at 5 |
Formula and method
Formula
bricks per ft² = 144 ÷ ((length + joint) × (height + joint)); mortar = wall volume − brick volume
IEEE-754 double precision; shown to the decimals indicated.
Enter the actual brick size; the mortar figure excludes waste and bed-joint overfill. Plan geometry only; confirm quantities with your supplier and local code before ordering.
Worked examples
These examples are verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Wall length = 20; Wall height = 8; Brick length = 7.625; Brick height = 2.25; Brick depth (wall thickness) = 3.625; Mortar joint = 0.375; Waste allowance = 5.
| Result | Value |
|---|---|
| Units needed | 1152 |
| Net wall area | 160 ft² |
| Mortar (cubic feet) | 8.85 |
Example 2
Inputs: Wall length = 30; Wall height = 10; Brick length = 8; Brick height = 2.667; Brick depth (wall thickness) = 4; Mortar joint = 0.375; Waste allowance = 10; Openings (optional) = 24.
| Result | Value |
|---|---|
| Units needed | 1717 |
| Net wall area | 276 ft² |
| Mortar (cubic feet) | 14.95 |
The first line is the headline result (units needed). Below it the brick Calculator lists net wall area and mortar (cubic feet), which describe the same case from other angles. IEEE-754 double precision; shown to the decimals indicated.
The count
Each brick with joints covers 8 × 2.625 = 21 in², so 144 ÷ 21 = 6.857 bricks per ft². For 160 ft² that is 1,097 bricks, and a 5% allowance gives 1,152.
Allowances
Subtract door and window openings and add 5 to 10% for breakage and cuts. A double-thickness wall doubles the count. Mortar volume is the wall volume minus brick volume.
How the result changes with wall length
Holding every other input at the first worked example, this table changes only wall length. It shows how sensitive the answer is to that one value; each row was produced by running this calculator.
| Wall length | Units needed | Net wall area | Mortar (cubic feet) |
|---|---|---|---|
| 10 | 576 | 80 ft² | 4.42 |
| 20 | 1152 | 160 ft² | 8.85 |
| 40 | 2304 | 320 ft² | 17.69 |
| 80 | 4608 | 640 ft² | 35.39 |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Wall length: entering "0" shows "Wall length must be greater than 0." beside that field and no result.
- Openings (optional): entering "200" shows "Openings cannot cover the whole wall." beside that field and no result.
Choosing between the Brick Calculator and similar calculators
Each row shows what a related calculator on this site asks for and what it returns, so you can pick the one that matches your question.
| Calculator | You enter | It returns |
|---|---|---|
| [Concrete Block Calculator](/construction/block-quantity-calculator/) | wall length, wall height and block length | Units needed |
| [Roof Pitch Calculator](/construction/roof-pitch-calculator/) | i know the and value | Pitch |
| [Tile Calculator](/construction/tile-calculator/) | area to tile, tile length and tile width | Tiles needed |
| [Aquarium Volume Calculator](/construction/aquarium-volume/) | length, width and water height | Capacity |
| [Flooring Calculator](/construction/flooring-calculator/) | room length, room width and waste allowance | Flooring to buy |
Background: construction estimates
Material quantities are geometry plus a margin. Calculate the exact volume or area, add an allowance for waste, spillage, cuts and uneven ground (calculator pages commonly mention 5 to 10 percent, a rule of thumb that varies by material and job) and round up to whole units. One cubic yard is exactly 27 cubic feet.
Suppliers often have minimum order sizes and may charge for small loads, so confirm quantities, product yields and local code with your supplier or a qualified estimator before ordering.
Assumptions and limitations
- Add 5–10% for breakage
Quantities are estimates. Add allowances for waste and site conditions, and follow local codes and a qualified professional's instructions for structural or safety-critical work.
If a required value is empty, not a number, or outside its allowed range, the form marks that field with a message and shows no result instead of a misleading number. The automated checks deliberately try invalid entries for wall length and openings (optional) to confirm this.
Frequently asked questions
How many bricks per square foot?
About 6.9 with standard modular bricks and 3/8 inch joints.
What is mortar for?
It bonds the bricks and fills the joints.
Do I count face bricks only?
Count all bricks in the wall thickness you build.
What does the Brick Calculator calculate?
Bricks and mortar volume for a wall. It returns Units needed, Net wall area and Mortar (cubic feet).
What formula does the Brick Calculator use?
bricks per ft² = 144 ÷ ((length + joint) × (height + joint)); mortar = wall volume − brick volume. Enter the actual brick size; the mortar figure excludes waste and bed-joint overfill.
What do I need to enter in the brick Calculator?
You enter Wall length (ft), Wall height (ft), Brick length (in), Brick height (in), Brick depth (wall thickness) (in), Mortar joint (in) and Waste allowance (%). Optional: Openings (optional) (ft²).
How is the result rounded or limited?
IEEE-754 double precision; shown to the decimals indicated. Add 5–10% for breakage.
What is an example of a brick result?
With wall length 20, wall height 8, brick length 7.625, brick height 2.25 and brick depth (wall thickness) 3.625, the units needed is 1152.
Can I rely on this calculator for a decision?
Quantities are estimates. Add allowances for waste and site conditions, and follow local codes and a qualified professional's instructions for structural or safety-critical work. For this calculator in particular: Add 5–10% for breakage.
Related calculators
- Concrete Block Calculator — Concrete blocks and mortar volume for a wall.
- Roof Pitch Calculator — Roof pitch as rise per 12 inches, angle, slope percent and rafter length factor.
- Tile Calculator — Number of tiles (and boxes) for an area.
- Aquarium Volume Calculator — Capacity and filled weight of a rectangular aquarium.
- Flooring Calculator — Flooring area with waste, and boxes if you know the coverage per box.
- Roof Shingles Calculator — Squares and bundles of shingles for a roof area.
- Siding Calculator — Squares of siding for walls after deducting openings.
- Clapboard Siding Calculator — Number of clapboard pieces from exposure and wall size.
- Construction Waste Calculator — Material to order after a waste allowance.
Sources
- OpenStax, Prealgebra 2e (Rice University): perimeter, area, volume, circumference and the Pythagorean theorem
- NIST Special Publication 811, Guide for the Use of the International System of Units (SI), Appendix B conversion factors (international foot 0.3048 m, inch 25.4 mm, US gallon 3.785411784 L)
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.