Brick Calculator
Estimate bricks, cement bags and sand for a wall from its size and thickness.
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About the Brick Calculator
Planning a boundary wall, a room or an extension? Enter the wall length, height and thickness to estimate the number of bricks and the cement and sand needed for the mortar.
The default brick size is the common Pakistani brick of 8.5 × 4.25 × 2.75 inches (9 × 4.5 × 3 inches with mortar), with a 3/8-inch joint and a 1 : 6 mortar mix. You can change all of these.
How to use the Brick Calculator
- Choose feet or metres and enter the wall length and height.
- Choose the wall thickness (4.5-inch half-brick or 9-inch full-brick wall, etc.).
- Enter the total area of doors and windows to deduct, if any.
- Adjust brick size, joint, mortar mix and wastage under More options if needed, then click Calculate bricks.
Formula
Wall volume = (length × height − openings) × thickness.
Bricks = wall volume ÷ volume of one brick with mortar, then wastage is added.
Mortar (wet) = wall volume − volume of the bricks themselves; dry mortar = wet × 1.33.
Cement = dry mortar ÷ (1 + sand parts); one 50 kg bag ≈ 0.0347 m³ (1.25 cft). Sand = dry mortar × sand parts ÷ (1 + sand parts).
Examples
- A wall 10 ft long, 10 ft high, 9 inches thick (75 cft): about 1,010 bricks + 5% = 1,061 bricks, 2.7 bags of cement and 19.3 cft of sand (1 : 6 mortar).
- The same wall at 4.5 inches thick needs about half the bricks.
Frequently asked questions
How accurate is this estimate?
It is a planning estimate based on standard formulas. Actual quantities depend on workmanship, material quality and site conditions, so confirm with your contractor or engineer before buying.
How many bricks are in one cubic foot?
With the standard 9 × 4.5 × 3 inch nominal size, about 13.5 bricks make one cubic foot of wall.
Why is the dry mortar volume 1.33 times the wet volume?
Cement and sand shrink when water is added because the gaps between particles fill up. The 1.33 factor (about 33%) is a common allowance.