Brick Calculator
Estimate how many bricks you need for a wall from its length and height, your brick size, and a wastage allowance. The calculator divides the wall area by the brick face area and adds your wastage percentage.
Formula
Bricks = (Wall Area ÷ Brick Face Area) × (1 + Wastage%)
- The wall area equals length × height, and each brick covers an area of its length × height (laid flat in the wall face).
- Dividing wall area by brick face area gives the raw number of bricks before any losses.
- The wastage percentage covers breakage, cutting, and laying errors — 10% is a common starting point.
- Brick dimensions are entered in millimetres and converted to metres internally.
- Openings such as doors and windows are not subtracted, so deduct them separately for large gaps.
6 m × 3 m wall with 190 × 90 mm bricks
Inputs
- Wall Length (m): 6
- Wall Height (m): 3
- Brick Length (mm): 190
- Brick Height (mm): 90
- Wastage (%): 10
Wall area = 18 m². Each brick face = 0.19 × 0.09 = 0.0171 m². 18 ÷ 0.0171 ≈ 1,053 bricks, plus 10% wastage ≈ 1,158 bricks.
Frequently asked questions
How many bricks do I need for a wall?
Divide the wall area by the area of one brick face, then add a wastage allowance. This calculator does that for you from your dimensions.
How much wastage should I allow?
Around 10% is typical for straightforward walls; allow 15% or more where there is lots of cutting around openings or curves.
Does it account for mortar joints?
Use the brick's nominal (coordinating) size — actual size plus a mortar joint — to factor in mortar. Otherwise the count will be slightly high.
Are doors and windows subtracted?
No. Calculate the area of any large openings and subtract their brick count separately for an accurate total.
Can I use imperial measurements?
Convert your figures to the units shown (metres for the wall, millimetres for the brick) before entering them.