Brick Calculator
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Find out how many bricks and bags of mortar you need for a wall by length, height, and door/window openings.
Quick answer: A 145 sq ft wall (net of openings) built with standard modular brick needs about 1,077 bricks after a 10% waste allowance, using the Brick Industry Association's 6.75 bricks-per-sq-ft coverage rate, plus roughly 9 bags of mortar mix at 8 bags per 1,000 bricks.
Total Bricks Needed
Includes waste allowance
Gross wall area: · Openings deducted:
📐 Formula
Net wall area = (length × height) − door/window openings. Bricks before waste = ceil(net area × 6.75 bricks per sq ft). Bricks total = ceil(bricks before waste × (1 + waste %)). Mortar bags = ceil(bricks total ÷ 1000 × 8 bags per 1,000 bricks).
How to Use the Brick Calculator
Enter wall length and height
Enter your wall's length and height in feet so the calculator can work out the gross wall area.
Enter door and window openings
Enter the total square footage of any doors, windows, or other openings so they're deducted from the gross area, since you don't need bricks or mortar to cover them.
Set your waste factor
Accept the 10% default or adjust it to match your project's complexity — simple rectangular walls need less waste allowance, walls with more cuts and corners need more.
Review bricks, mortar, and cost
Review the total bricks needed, mortar bags required, and an estimated material cost range for your project.
Why Standard Modular Brick Needs About 6.75 Bricks per Square Foot
The vast majority of US residential brickwork uses standard modular brick — a specified size of about 3⅝ × 2¼ × 7⅝ in. that, once you add a standard 3/8 in. mortar joint on every side, rounds up to a clean nominal size of 4 × 2⅔ × 8 in. The Brick Industry Association's Technical Note 10, the trade's own reference for estimating brick and mortar quantities, lists 675 modular bricks per 100 sq ft of single-wythe wall area laid in running or stack bond — which is exactly where this calculator's 6.75-bricks-per-square-foot default comes from. That figure already accounts for the mortar joint itself; it's a coverage rate for finished wall area, not just the brick footprint alone.
Not every brick is modular-sized, though. Engineer modular brick, at a taller 3⅕ in. nominal height, covers more wall per brick and needs closer to 5.6 bricks per sq ft, while utility brick — a bigger 4 × 4 × 12 in. format — needs only about 3 bricks per sq ft. If your project uses a non-standard brick, adjust your own count accordingly using the same wall-area method: divide 100 sq ft by your brick's specific published coverage rate.
How Much Mortar Do You Really Need?
Masons commonly use a straightforward rule of thumb for mortar: about 8 bags of pre-mixed mortar per 1,000 modular bricks laid with a standard 3/8 in. joint. This figure shows up in two independent industry references — the Brick Industry Association's own "8 bags of masonry cement per 1,000 brick" guidance, and Riverside Brick & Supply's published masonry estimating guide, which lists the same 8-bags-per-1,000-brick figure for modular face brick specifically. Because both sources land on the same number, this calculator uses it as its mortar-quantity basis, applied to your total brick count including waste — since every brick you actually lay, waste replacement bricks included, needs its own bed of mortar.
Mortar quantity does shift with joint width — a wider 1/2 in. joint needs meaningfully more mortar per brick than the standard 3/8 in. joint this calculator assumes, and BIA's own technical note recommends adding a separate 15–25% mortar waste allowance on top of the base quantity for spillage and mixing loss. This calculator folds its estimate into the brick waste factor rather than tracking mortar waste separately, so treat the mortar bag count as a solid planning figure to round up from, not a to-the-bag exact order.
Why a Waste Factor Matters
No brick wall uses only whole, uncut bricks. Every corner, every course that has to line up with a door or window opening, and every accidental drop or crack on site eats into your brick count beyond the pure math of area × coverage rate. The Brick Industry Association recommends at least 5% added to net brick quantities as a general rule, and Riverside Brick & Supply's estimating guide recommends a broader 5–10% across brick, block, and mortar quantities alike for breakage, spillage, and estimating error. This calculator defaults to 10%, the upper end of that commonly cited range, since it's a safer starting point for a first-time DIY estimate — you can always dial it down for a simple, low-waste rectangular wall once you're confident in your own cutting accuracy.
Complex layouts need more than the default. A wall with many corners, a bond pattern with headers, or a curved or stepped design wastes more brick per linear foot than a straight, uninterrupted run — the same principle that pushes this site's paving calculator to a 15% wastage allowance for herringbone layouts instead of the 10% used for a simple grid.
Worked Example: A 20 ft × 8 ft Wall with 15 Sq Ft of Openings
Take a wall 20 ft long and 8 ft high, with 15 sq ft of combined door and window openings to deduct, using the 10% default waste factor:
Gross wall area = 20 ft × 8 ft = 160 sq ft.
Net wall area = 160 sq ft − 15 sq ft = 145 sq ft — matching the Quick Answer above.
Bricks before waste = ceil(145 × 6.75) = ceil(978.75) = 979 bricks.
Bricks with 10% waste = ceil(979 × 1.10) = ceil(1,076.9) = 1,077 bricks.
Mortar needed = ceil(1,077 ÷ 1000 × 8) = ceil(8.616) = 9 bags (80 lb).
Estimated material cost = (1,077 bricks × $0.40–$0.90) + (9 bags × ~$12) ≈ $539–$1,077.
A larger or smaller wall scales the same way — the openings deduction and waste factor apply proportionally, since every quantity in this calculator is driven directly by net wall area.
Bricks & Mortar Needed by Wall Area
For a quick planning reference before you measure your own wall precisely, here's how brick and mortar quantities scale across common wall areas, using the same 6.75-bricks-per-sq-ft coverage rate and 10% waste factor as this calculator's defaults.
| Net Wall Area | Bricks (no waste) | Bricks (10% waste) | Mortar Bags (80 lb) |
|---|---|---|---|
| 100 sq ft | 675 | 743 | 6 |
| 250 sq ft | 1,688 | 1,857 | 15 |
| 500 sq ft | 3,375 | 3,713 | 30 |
| 750 sq ft | 5,063 | 5,570 | 45 |
| 1,000 sq ft | 6,750 | 7,425 | 60 |
| 2,000 sq ft | 13,500 | 14,850 | 119 |
DIY Bricklaying vs. Hiring a Mason
This calculator estimates materials, not labor or installed cost — bricklaying is a genuinely skilled trade, and a wall that isn't laid level, plumb, and with consistent joints will show every flaw permanently once the mortar cures. For a small, low, freestanding wall (a garden border, a mailbox pillar) a patient DIYer with the right tools and a practice course or two can get a workable result. For anything structural, load-bearing, tall, or highly visible — a house wall, a retaining structure, a chimney — hiring a licensed mason is worth the added cost, since the labor-intensive nature of bricklaying means installed cost typically runs well above material cost alone.
Once you've worked out your brick and mortar needs, it's worth planning the rest of a masonry or hardscaping project too. If your project also includes a tiled surface, our tile calculator works out tile count, thin-set mortar, and grout the same way this tool works out bricks and mortar. If it extends outdoors to a patio or walkway instead, our paving calculator covers paver count, bedding sand, and jointing sand using the same area-based approach. Browse every tool in this category on our renovation calculators hub.
Frequently Asked Questions
For a standard US modular brick (nominal 4×2⅔×8 in., laid with a 3/8 in. mortar joint) in a single-wythe wall with running bond, you need about 6.75 bricks per square foot of net wall area, per the Brick Industry Association's Technical Note 10 estimating tables. That works out to roughly 675 bricks per 100 sq ft before any waste allowance. Larger or non-modular brick sizes need fewer bricks per square foot, and smaller sizes need more, so always confirm the coverage rate for your specific brick before ordering.
A commonly used masonry rule of thumb, corroborated by both the Brick Industry Association and Riverside Brick & Supply's estimating guide, is about 8 bags of 80 lb pre-mixed mortar per 1,000 modular bricks laid with a standard 3/8 in. joint. For a 1,000-brick wall that's roughly 8 bags; smaller jobs scale down proportionally. Actual mortar use varies with joint width, mixing waste, and how much mortar squeezes out of the joints during laying, so treat this as a solid planning estimate rather than an exact figure.
Industry guidance commonly cites 5–10% for brick waste from cutting, breakage, and on-site errors, with the Brick Industry Association recommending at least 5% as a baseline and more for complex layouts. This calculator defaults to 10%, in the middle of that commonly cited range, but you can adjust it lower for a simple rectangular wall with few cuts, or higher for a wall with many corners, curves, or a bond pattern that wastes more material per brick.
A standard US modular brick has a nominal size of 4 in. wide × 2⅔ in. high × 8 in. long, with a specified (actual) size of about 3⅝ × 2¼ × 7⅝ in. — the nominal size is simply the specified brick plus a 3/8 in. mortar joint on each dimension, per the Brick Industry Association's Technical Note 10. This is by far the most common brick size used in US residential construction, and it's the size this calculator's default coverage rate is based on.
Standard clay face brick material costs roughly $0.40 to $0.90 per brick as of 2026, according to HomeGuide's brick pricing data, with the price depending on brick type, color, and region. That's material cost only — a fully installed brick wall, including labor, typically runs far higher per square foot than materials alone, since bricklaying is skilled, labor-intensive work. Get a local mason's quote for an installed-cost estimate rather than relying on material pricing alone.
Sources & Methodology
The 6.75-bricks-per-sq-ft coverage rate and the 5%+ brick waste guidance come from the Brick Industry Association's Technical Note 10 (Table 4), the masonry trade's own reference for dimensioning and estimating brick masonry. The 8-bags-of-mortar-per-1,000-brick figure is corroborated across two independent industry sources — BIA's own rule of thumb and Riverside Brick & Supply's published masonry estimating guide. The $0.40–$0.90 per-brick cost range is drawn from HomeGuide's 2026 brick pricing data and is a material-only estimate, not an installed cost. This tool was built on these published industry references, the same basis this category's other material calculators (Paint Coverage, Tile, Paving) use — not a keyword-volume justification. Actual quantities and pricing vary by brick size, joint width, region, and supplier; verify against your specific supplier's specs before ordering.