Calculator
Brick Calculator
A brick wall is not measured in bricks. It is measured in square feet, and then converted at a rate that depends entirely on the size of brick you buy and how thick the mortar joints are. That rate is why two people building the same 160 square foot wall can come back from the yard with counts 20% apart and both think they measured correctly.
This calculator does the conversion properly: it works out how much wall face one brick actually occupies once its joints are included, turns that into bricks per square foot, and applies it to your net wall area. It also tells you how many courses high the wall will run, because a course count is the fastest way to sanity-check a brick order against the wall you can see.
Calculate your quantity
Total square feet of openings to deduct.
7-5/8 in is a standard modular brick.
10% covers cuts, breakage in transit, and an attic stash for future repairs.
Bricks needed
1,207 bricks
- Net wall area
- 160 sq ft
- Bricks per sq ft
- 6.86 bricks/sq ft
- Courses high
- 37 courses
- Before waste
- 1,098 bricks
- A 7.625 x 2.25 in brick with 0.375 in joints works out to 6.86 bricks per square foot of wall face.
Shopping summary
- • 1207 bricks (about 3 strapped cubes of 500)
This is an estimate — confirm structural work with a professional.
How this calculation works
Bricks are made undersized on purpose. A modular brick measures 7 5/8 by 2 1/4 inches on its face, and it is meant to be laid with a 3/8 inch joint — which brings the space it occupies to exactly 8 by 2 5/8 inches. That deliberate undersizing is what lets bricklayers work to round module dimensions while the units themselves are odd numbers.
So the unit of area that matters is not the brick, it is the brick plus one joint in each direction. Divide 144 square inches by that figure and you have bricks per square foot: for a modular brick at a 3/8 inch joint, 6.86. Multiply by the net wall area, add waste, and you have an order. Widen the joint to 1/2 inch and the same brick drops to 6.55 per square foot, which is a 5% smaller order on the same wall.
- Openings come off the gross area first. A standard door is about 21 square feet and a window 12 to 16, and on a small wall those deductions are a meaningful share of the order.
- Wythes multiply. A single-wythe veneer is one brick thick; a solid two-wythe wall needs double the count, and the calculator's wythe field is there rather than expecting you to double the answer yourself.
- The course count is your check. Wall height in inches divided by 2 5/8 tells you how many courses you are laying, and a course that lands on an awkward fraction usually means the wall height wants adjusting before anything is ordered.
The formula
bricks = (wall area − openings) × 144 ÷ ((brick length + joint) × (brick height + joint)) × wythes × (1 + waste)
- wall area
- Wall length times wall height, in square feet, measured on the face you are laying.
- openings
- Total square feet of doors and windows deducted before any conversion happens.
- brick length + joint
- The horizontal module: the brick's own length plus one mortar joint, because each brick carries one joint's worth of space with it along the course.
- brick height + joint
- The vertical module: the brick's height plus one bed joint. For modular brick at 3/8 inch this is 2 5/8 inches, which is why three courses make exactly 8 inches.
- 144
- Square inches in a square foot — the conversion that turns a module in inches into a rate per square foot.
- wythes
- How many bricks thick the wall is. Veneer is one; a structural solid wall is two or more.
- waste
- The share broken in transit, cut at openings and corners, or set aside for future repairs. Ten per cent is the working default for a plain running-bond wall.
The joint appears once per brick in each direction, not twice. It is tempting to add a joint to both ends of the brick, but every joint is shared between two neighbouring units — count it twice and you will under-order by roughly 5%, which on a thousand-brick wall is fifty bricks you do not have on the last afternoon.
Where these numbers come from
- 7 5/8 × 2 1/4 in modular brick
- ASTM C216 nominal modular sizing, the size sold as standard across North America. Queen (7 5/8 × 2 3/4), king and utility brick are all offered too, which is why the dimensions here are inputs rather than constants.
- 6.86 bricks per square foot
- Derived on this page from the module rather than looked up: 144 ÷ (8.0 × 2.625). It matches the figure brick suppliers quote for modular brick at a 3/8 inch joint, which is a useful independent check on the arithmetic.
- 3/8 in mortar joint
- The joint width modular brick is dimensioned around, and the default across the trade. Joint widths from 1/4 to 1/2 inch are all used; the calculator takes it as an input because it moves the answer several per cent.
- 500 bricks per strapped cube
- Common palletised bundle size at builders' merchants. Bundles of 400 and 512 are also sold, so treat the cube count as a rough purchasing unit rather than an exact one.
- 10% waste
- Trade convention for a plain running-bond wall with few openings. Raise it toward 15% for heavy cutting around openings, decorative bonds, or reclaimed brick, which arrives with a higher breakage rate.
Worked examples
A plain 20 by 8 foot garage wall in modular brick
| Wall length | 20 ft |
|---|---|
| Wall height | 8 ft |
| Door and window area | 0 sq ft |
| Brick length | 7.625 in |
| Brick height | 2.25 in |
| Mortar joint | 0.375 in |
| Wythes (layers thick) | 1 |
| Waste factor | 10 % |
| Bricks needed | 1207 bricks |
|---|---|
| Net wall area | 160 sq ft |
| Bricks per sq ft | 6.86 bricks/sq ft |
| Courses high | 37 courses |
| Before waste | 1098 bricks |
160 square feet of unbroken wall at 6.86 bricks per square foot is 1,097 bricks before anything is allowed for breakage. The 10% waste factor takes it to 1,207, which is between two and three strapped cubes — and this is exactly the situation where it is worth knowing your supplier's bundle size, because rounding up to a full cube may cost less than a part bundle plus a delivery.
The 37 courses in that wall are the check worth doing. At 2 5/8 inches a course, 37 courses is 97 1/8 inches, which is just over the 96 inch wall you asked for — so the top course will need to be cut, or the wall height nudged. Finding that before the order is placed rather than on the last day is most of the value of running the numbers at all.
A house wall in queen brick, with a door and two windows
| Wall length | 24 ft |
|---|---|
| Wall height | 9 ft |
| Door and window area | 45 sq ft |
| Brick length | 7.625 in |
| Brick height | 2.75 in |
| Mortar joint | 0.375 in |
| Wythes (layers thick) | 1 |
| Waste factor | 12 % |
| Bricks needed | 1104 bricks |
|---|---|
| Net wall area | 171 sq ft |
| Bricks per sq ft | 5.76 bricks/sq ft |
| Courses high | 35 courses |
| Before waste | 985 bricks |
This wall is larger — 216 square feet against 160 — and still takes fewer bricks, for two reasons that pull in the same direction. Queen brick is half an inch taller in the face, which drops the rate from 6.86 to 5.76 bricks per square foot, and 45 square feet of openings comes off before any conversion happens. Together those take the count below the smaller wall's.
Waste is set at 12% rather than 10% here because openings mean cutting. Every jamb and every sill is a line of cut brick, and a cut brick very rarely yields a usable second piece in a running bond. If this wall had a soldier course over the openings or a rowlock sill, 15% would be the safer figure.
Common mistakes
- Counting the joint twice. Adding a joint to both ends of a brick and both its top and bottom looks careful and under-orders by about 5%, because each joint is shared between two bricks.
- Using a bricks-per-square-foot figure from a different brick. The 6.86 figure everyone quotes is specifically modular brick at a 3/8 inch joint. Queen brick at the same joint is 5.76, and a thin veneer brick is different again.
- Measuring the wall rather than the wall face. On a gable, the triangle above the plate is half base times height — measuring the full rectangle over-orders substantially, and measuring only the rectangle under the plate leaves the gable unbuilt.
- Forgetting that the wall has ends. A wall that returns around a corner needs the corner counted once, not on both faces, and a wall that stops needs a soldier or return detail that is not in a plain area calculation at all.
- Ordering exactly what the calculator says on a wall you will still be repairing in ten years. Brick colour is a fired product of a specific clay and a specific kiln run, and the same product number two years later will not match. The waste allowance is also the repair stash.
Shopping summary
Order the brick count including waste, rounded up to whole bundles if the part-bundle price is close to a full one. Mortar is a separate calculation driven by the unit count rather than the wall area — the mortar mix calculator takes the number this page produces and converts it into bags at your joint width.
Also worth having on the delivery: wall ties at roughly one per two square feet for a veneer, weep vents at 24 inch centres along the base course, and a bag more mortar than the arithmetic asks for. If the wall involves a corner, check whether the brick is sold with matching corner units or whether every corner brick is cut on site.
If this brick is going on a wall you are also building, the concrete block calculator handles the backup wythe, and the stone veneer calculator covers the case where the facing is a manufactured product sold by the box rather than by the brick.
FAQ
Why does my supplier quote 7 bricks per square foot when this says 6.86?
Because 7 is the rounded working figure and it builds in a small cushion. On a 160 square foot wall the difference is 22 bricks, which is under the waste allowance either way — so both numbers land in the same place for ordering. Use the precise figure when you are comparing two brick sizes against each other, where a 2% error compounds.
Does the mortar joint width really change the brick count that much?
It changes it about 5% between a 3/8 and a 1/2 inch joint on modular brick. That is small relative to your waste factor, so it will not decide whether you have enough — but it matters when the joint width is set by matching an existing wall, because then the module changes and so does the course height, which affects where the wall lands relative to a window head.
How do I work out the brick for a gable end?
Split it: the rectangle below the plate is length times height, and the triangle above is half the base times the vertical rise. Add them, then treat the result as your wall area. Gables also need a higher waste factor than a rectangular wall, because every course in the triangle ends in an angled cut at both ends.
What is a wythe, and do I have one or two?
A wythe is one continuous vertical layer of brick. Almost all modern residential brickwork is a single-wythe veneer tied back to a framed or block wall behind it, so the answer is usually one. Two-wythe solid brick walls are common in older housing and in some garden walls, and they take double the brick plus header courses tying the two layers together.
Can I use this for thin brick veneer?
Yes, if you enter the actual face dimensions of the thin brick, which are usually the same as full brick even though the unit is only half an inch to an inch deep. Set wythes to one. What this page will not tell you is the corner piece count — thin brick corners are sold separately by the linear foot, in the same way the stone veneer calculator handles them.
Should the waste factor go up for a decorative bond?
Yes, and sometimes sharply. Running bond wastes least because a cut brick at one end of a course is often usable at the other. Herringbone, basketweave and stack bond with a pattern all generate offcuts that fit nowhere, and 15 to 20% is realistic. The waste factor calculator works the figure out from your layout rather than asking you to pick one.
Where to go next
The projects this number is a step of, the guides that explain the method behind it, and the rest of its trade group.