Calculate the number of bricks needed for a wall, accounting for the mortar joint thickness and a wastage allowance.
Brick Size (mm)
How to Use the Brick Calculator
Enter the "Wall Length", "Wall Height", and "Wall Thickness".
Enter your brick's "Length", "Width", and "Height" - defaults are for a standard modular brick.
Enter the "Mortar Joint" thickness between bricks.
Enter a "Wastage (%)" allowance for broken or cut bricks.
Click "Calculate Bricks" to see the total number of bricks needed.
How the Brick Count Is Worked Out
This calculator uses the volume method, which is how most site engineers and BOQ estimates in India arrive at a brick count.
Wall volume = Length × Height × Thickness, with the thickness converted from millimetres to metres.
Each brick is enlarged by one mortar joint in every direction. A 190 × 90 × 90 mm brick with a 10 mm joint becomes a 200 × 100 × 100 mm unit, which is 0.002 m³.
Bricks = Wall volume ÷ Volume of one brick-plus-mortar unit.
The wastage percentage is added on top and the answer is rounded up to a whole brick.
Because the joint is added to all three sides, the same calculation also tells you how much of the wall is mortar. For a modular brick with a 10 mm joint, the brick itself fills about 77% of the unit volume and the remaining 23% or so is wet mortar.
Worked Example
A boundary wall 5 m long and 3 m high, built 230 mm thick with 190 × 90 × 90 mm bricks, 10 mm joints and 5% wastage: wall volume = 5 × 3 × 0.23 = 3.45 m³. One brick with mortar = 0.2 × 0.1 × 0.1 = 0.002 m³, so 3.45 ÷ 0.002 = 1,725 bricks. Adding 5% gives 1,811.25, which rounds up to 1,812 bricks.
Bricks are usually priced per thousand in India, so in practice you would order about 1,850 to 1,900 to keep a few spare for later repairs and for the bricks that arrive chipped.
Bricks per Cubic Metre for Common Sizes
Results with a 10 mm mortar joint and no wastage. Brick sizes from local kilns vary, so measure a few bricks from your actual supply before ordering.
Brick size (mm)
Bricks per m³
Per m² of 230 mm wall
Per m² of 115 mm wall
190 × 90 × 90 (IS modular)
500
115
58
230 × 110 × 70
434
100
50
230 × 115 × 75
392
90
45
225 × 112.5 × 75
409
94
47
IS 1077 specifies the 190 × 90 × 90 mm modular brick, but many kilns still supply the older, larger traditional sizes. Larger bricks mean fewer pieces per wall, so a count worked out for one size will be wrong for another.
Tips for a More Accurate Order
Match the wall thickness to the brick. With traditional 230 mm bricks, a full-brick wall is 230 mm and a half-brick partition is about 115 mm. With modular bricks, the equivalent walls are nearer 200 mm and 100 mm, measured without plaster.
Subtract openings. Work out the area of doors, windows and ventilators, multiply by the wall thickness, and reduce the wall volume before calculating. Lintels and beams that run through the wall also displace bricks.
Use 5% wastage for machine-made or wire-cut bricks delivered on pallets. For hand-moulded country bricks, which break more in transport and stacking, 7–10% is safer.
Order cement and sand separately. Since roughly a quarter of the wall volume is mortar, a 3.45 m³ wall needs close to 0.8 m³ of wet mortar, and the dry ingredients are more than that because sand and cement shrink in volume when mixed with water.
For fly ash bricks or AAC blocks, enter the block size in the brick fields. The method is the same, though AAC blocks are often laid with thin adhesive joints of 2–3 mm instead of 10 mm mortar.
Frequently Asked Questions
Each brick occupies more space in the wall than its own dimensions once the mortar joint around it is included. This calculator adds the mortar thickness to each brick dimension before computing how many "brick + mortar" units fit into the wall volume.
A 9-inch wall is approximately 230mm thick (one full brick length), while a 4.5-inch (half-brick) wall is approximately 115mm thick - commonly used for partition walls.
No, this calculator assumes a solid wall. Use the Wall Area Calculator to work out the net wall area after deducting doors and windows, then scale down your brick count proportionally.
With a 10 mm mortar joint, about 500 modular bricks of 190 × 90 × 90 mm fit in 1 m³. With a traditional 230 × 115 × 75 mm brick, it is about 392. Add your wastage allowance to either figure.
Around 5% is usual for good-quality machine-made bricks. Hand-moulded bricks, long transport distances or walls with many cuts around openings and corners can justify 7–10%.