Brick Calculator
Calculate how many bricks a wall needs from its dimensions, with mortar joint and wastage allowance.
Formula last reviewed 4 August 2026 · How we verify our calculators
Bricks required
3623 bricks
Updates live as you type
Frequently asked questions
The calculator divides the wall volume by the volume of one brick including its mortar joint, then adds a wastage allowance. A standard brick with mortar occupies about 0.002 m³, giving roughly 500 bricks per cubic metre.
A 9-inch (full-brick) wall is about 0.23 m and a 4.5-inch (half-brick) wall about 0.115 m. The thickness strongly affects the brick count.
Bricks are laid with mortar between them, so each effectively occupies a slightly larger space (about 20 × 10 × 10 cm with a 1 cm joint). Ignoring it overestimates the count.
A 5–10% allowance covers breakage, cutting and handling losses. Increase it for complex walls with many openings and cuts.
Three thousand six hundred bricks for a wall
A wall 10 m long, 3 m high and 0.23 m thick, with 5% wastage, needs about 3,623 bricks.
The 0.23 m thickness is the standard 9-inch wall used for external and load-bearing walls in India. A 4.5-inch (0.115 m) wall — used for internal partitions — needs roughly half as many.
How the count is derived
Wall volume = length × height × thickness = 10 × 3 × 0.23 = 6.9 m³
A standard Indian brick is 190 × 90 × 90 mm, and with a 10 mm mortar joint on each face the effective size becomes 200 × 100 × 100 mm = 0.002 m³.
Bricks = wall volume ÷ brick volume with mortar = 6.9 ÷ 0.002 = 3,450
Add 5% wastage for breakage, cutting at openings and handling losses: 3,450 × 1.05 ≈ 3,623 bricks.
Note the mortar joint doing real work here. Without it, a brick occupies 0.001539 m³ and the same wall would need about 4,484 bricks — a 30% difference. Any brick calculation that ignores the joint substantially over-orders.
Mortar, and what else to order
The mortar volume is the difference between the wall volume and the volume of the bricks themselves — roughly 20–25% of the wall for a 10 mm joint. For this wall that is about 1.5 m³ of mortar.
At a typical 1 : 6 cement-sand mortar for 9-inch walls, that needs roughly 10–12 bags of cement and about 1.5 m³ of sand, before wastage. Richer mixes of 1 : 4 are used for load-bearing or exposed work.
Deduct openings before ordering: a standard door of about 2.1 × 0.9 m and windows of 1.2 × 1.2 m each remove a meaningful number of bricks from a wall this size.
Brick types
Clay bricks — the traditional choice, strong and durable, with quality varying considerably by kiln. First-class bricks should be well burnt, uniform in colour, free of cracks, and should ring when struck.
Fly ash bricks — more dimensionally consistent, lighter, requiring less mortar and less plaster, and increasingly favoured for their environmental profile. Slightly different water absorption behaviour, so soaking practice differs.
AAC blocks — autoclaved aerated concrete, far larger and lighter than bricks, with good thermal insulation. A block wall goes up considerably faster with much less mortar, though the material cost per unit volume is higher and fixings need specific anchors.
Reading the result
The count is an estimate for ordering. In practice, order 5–10% over the calculated figure — more for a wall with many openings, since cutting generates breakage.
Soak clay bricks before laying. Dry bricks draw water out of the mortar, preventing proper hydration and producing a weak bond that shows up as efflorescence and poor strength later. Soaking for a few hours until saturated but surface-dry is the standard practice, and one of the most frequently skipped steps on small sites.
Common mistakes
Ignoring the mortar joint. It changes the count by about 30%.
Not deducting openings. Doors and windows remove real volume.
Ordering exactly. Breakage and cutting are certain.
Laying dry bricks. The mortar bond fails without soaking.
Mixing brick sizes. Non-standard bricks change every figure here; measure a sample before ordering.