What Is a Brick Calculator?
A brick calculator estimates how many bricks and how much mortar a wall requires, based on the wall's dimensions, the brick size you're using, and the mortar joint thickness between courses. Brick sizing isn't standardized the way lumber is — Modular, Standard, Queen, King, and Utility bricks are all common, and each covers a different amount of wall per unit, so the "right" brick count depends entirely on which size you pick.
This tool also subtracts door and window openings from the wall area and applies a waste factor, since broken bricks, cuts at corners, and the occasional dropped brick are a normal part of any job — not a sign something went wrong. Brick dimensions themselves follow published industry specifications rather than a single universal standard, which the Brick Industry Association's Technical Notes lay out in detail for anyone sourcing brick in the US.
How to Use This Calculator
- Select a brick type — Modular, Standard, Queen, King, or Utility
- Enter wall length and height in feet
- Set mortar joint thickness — 3/8 inch (0.375") is the US standard default
- Add any doors or windows to subtract their area from the total wall
- Set a waste factor — 5-10% covers most straightforward walls
- Click "Calculate Bricks" to see bricks needed, net wall area, mortar volume, and mortar bag count
Bricks-Per-Square-Foot Formula
Every brick size reduces to the same core idea: take the brick's face dimensions, add the mortar joint on two sides, and see how many of those "nominal" rectangles tile one square foot:
That 6.86 figure is specific to Modular brick at exactly 7.625" long — a brick that measures 7.5" instead (some manufacturers round differently) would tile slightly differently. Always cross-check the "bricks per sq ft" number against your actual product's spec sheet before ordering in bulk.
Bricks Needed by Wall Size
Using Modular brick throughout, 3/8" joint, 10% waste, no openings subtracted — every row calculated independently, not scaled from a base number:
| Wall Size | Area | Bricks (no waste) | Bricks (10% waste) |
|---|---|---|---|
| 10 ft × 8 ft | 80 sq ft | 549 | 604 |
| 15 ft × 8 ft | 120 sq ft | 823 | 906 |
| 20 ft × 8 ft | 160 sq ft | 1,097 | 1,207 |
| 20 ft × 10 ft | 200 sq ft | 1,371 | 1,509 |
| 30 ft × 8 ft | 240 sq ft | 1,646 | 1,811 |
| 40 ft × 8 ft | 320 sq ft | 2,194 | 2,414 |
Doubling the wall length from 20 to 40 ft exactly doubles the brick count — 1,207 to 2,414 — since brick count scales linearly with area once the brick size and joint are fixed. Height works the same way: the 20×10 row needs 302 more bricks than the 20×8 row (1,509 minus 1,207), matching the extra 40 sq ft at roughly 6.86 bricks per sq ft, with waste applied.
Brick Type Comparison — Same Wall, Different Brick
Same 160 sq ft wall (20 ft × 8 ft), 3/8" joint, 10% waste — only the brick type changes:
| Brick Type | Actual Size (in) | Bricks/Sq Ft | Bricks Needed (10% waste) |
|---|---|---|---|
| Modular | 3.625 × 2.25 × 7.625 | 6.86 | 1,207 |
| Standard | 3.625 × 2.25 × 8.0 | 6.55 | 1,153 |
| Queen | 3.0 × 2.75 × 7.625 | 5.76 | 1,014 |
| King | 3.0 × 2.625 × 9.625 | 4.80 | 845 |
| Utility | 3.625 × 3.625 × 11.625 | 3.00 | 528 |
Switching from Modular to Utility brick on the identical wall cuts the brick count by 679 (1,207 minus 528) — more than half — because each Utility brick's face covers roughly 2.3 times the area of a Modular brick's face. Fewer, larger bricks mean less cutting and faster laying, which is exactly why Utility brick shows up often in larger commercial veneer work where speed matters more than the finer, more traditional look of Modular coursing. Standard nominal and actual brick dimensions for facing brick are codified in ASTM C216, the specification most US brick manufacturers build to.
Mortar Volume and Bag Count
Mortar volume isn't estimated from a fixed ratio here — it's the wall volume left over once the bricks themselves are subtracted out:
For the 966-brick wall above, that works out to roughly one 80-lb bag of mortar per 161 bricks. That ratio isn't fixed, though — it shifts with joint thickness and brick size, which is why the calculator recomputes mortar volume from scratch for every input rather than applying one blanket rule of thumb. Mortar types themselves (Type N, S, M, and O) are classified by compressive strength under ASTM C270, which is worth checking before assuming any mortar bag is interchangeable with another.
How Joint Thickness Changes the Count
Mortar joints aren't always exactly 3/8". Thinner joints mean more bricks fit per square foot; thicker joints mean fewer. Same 160 sq ft Modular-brick wall, only the joint changes:
| Joint Thickness | Bricks/Sq Ft | Bricks Needed (10% waste) |
|---|---|---|
| 1/4" (0.25 in) | 7.31 | 1,288 |
| 3/8" (0.375 in) — standard | 6.86 | 1,207 |
| 1/2" (0.5 in) | 6.44 | 1,135 |
Going from a 1/4" to a 1/2" joint on this wall drops the brick count by 153 (1,288 minus 1,135) — a thicker joint literally means less brick and more mortar for the same footprint, which matters both for material cost and for the visual weight of the mortar lines in the finished wall.
6 Practical Tips for Ordering Brick
- Order in full cube quantities when possible. Bricks are typically palletized in cubes of 500. A 966-brick order rounds up to two cubes (1,000 bricks) from most suppliers — check with your specific yard, since cube sizes vary.
- Buy 5-10% extra even beyond the calculator's waste factor for future repairs. Brick runs vary by production batch (called a "run" or "lot"), and matching a color years later is difficult to impossible if you didn't keep spares from the original order.
- Confirm actual dimensions with your supplier before ordering at scale. The 6.86 bricks/sq ft figure above assumes a 7.625" long Modular brick — a 1/8" difference in any dimension shifts the bricks-per-sq-ft number and, at 1,000+ bricks, can mean a real difference in total count.
- Bigger bricks aren't automatically cheaper per wall. Utility brick needs 528 units for the 160 sq ft wall above versus 1,207 Modular bricks — but Utility bricks typically cost more per unit, so compare total delivered cost per wall, not just per-brick or per-pallet pricing.
- Mortar color matters as much as brick color. The same brick with a light gray mortar versus a dark charcoal mortar can look like two different products entirely — request a small sample panel before committing to a full order if the finished look matters.
- Double-wythe and veneer walls need two separate calculations. Run this calculator once per layer (structural wythe, then veneer, or inner and outer wythes) rather than doubling one result, since layers can use different brick types or joint thicknesses.