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.
Halve the wall thickness, halve the brick order
A wall 10 m long, 3 m high and 0.23 m thick — a standard 9-inch wall — needs 3,623 bricks including a 5% wastage allowance: 10 × 3 × 0.23 = 6.9 m³ of wall volume, divided by the mortar-inclusive brick volume of roughly 0.002 m³, gives about 3,450 bricks before wastage. Switch to a 4.5-inch (0.115 m) partition instead, same length and height, and the brick count roughly halves too — wall volume, and therefore brick count, scales directly with thickness.
Why the mortar joint gets counted, not just the brick
A standard brick isn't laid brick-to-brick — a mortar joint sits between each one, so the effective footprint of a 19 × 9 × 9 cm brick with a 1 cm joint is closer to 20 × 10 × 10 cm, roughly 0.002 m³. That works out to about 500 bricks per cubic metre of finished brickwork, a figure experienced masons recognise on sight. Skip the joint in the calculation and the estimate undercounts what a real wall actually needs.
The one input that changes the answer more than any other
Wall thickness drives the brick count more than length or height individually, because it's the dimension most likely to be set incorrectly by habit rather than by the actual wall spec — a 9-inch (0.23 m) load-bearing wall needs far more bricks than a 4.5-inch (0.115 m) partition of the same face area, so confirming this figure against the actual drawing matters more than double-checking length or height.
This is an estimate for planning purposes. Always add a wastage margin and confirm exact quantities with your contractor or engineer before ordering materials. Openings for doors and windows reduce the real count, which this simple volume method doesn't subtract. Pair it with the cement calculator to estimate mortar materials too, so sand and cement for the joints get ordered alongside the bricks rather than discovered as a shortfall partway through the wall.