Brick Calculator (Bricks, Cement & Sand for Walls)
Work out how many bricks, cement bags and how much sand a wall needs, for 4.5, 9 or 13.5 inch walls with 1:4 or 1:6 mortar.
Compare thickness and mortar mix (same wall)
| Wall | Bricks (+wastage) | Cement 1:4 | Cement 1:6 | Sand 1:6 |
|---|---|---|---|---|
| 4.5" | 1,032 | 3.6 bags | 2.6 bags | 19.2 cft |
| 9" | 2,064 | 7.2 bags | 5.1 bags | 38.4 cft |
| 13.5" | 3,096 | 10.8 bags | 7.7 bags | 57.6 cft |
Optional: material cost
Prices change weekly. Enter today's rates from your local supplier.
Method verified Oct 2026 · Standard volumetric method for brick masonry (wet-to-dry factor 1.33, 50 kg bag ≈ 1.25 cft) as used in material-quantity handbooks; brick size per Punjab brick-size regulation reports.
- Using the 9×4.5×3 size without the mortar joint. That counts too many bricks.
- Forgetting to deduct doors and windows, or deducting them twice when walls meet at corners.
- Buying cement for masonry only and forgetting plaster on both faces.
- Ordering no spare bricks. Broken and cut bricks are normal, so add 5% or more.
- →Count and measure 10 bricks from the delivery; undersized bricks raise the count.
- →Soak bricks before laying so they don't suck water out of the mortar.
- →Use cement within about 3 months of manufacture and store bags off the floor.
- →Building a whole house? Get the full budget in the House Construction Cost Calculator.
This tool is for informational purposes only. Always verify results with a qualified professional.
What is the Brick Calculator (Bricks, Cement & Sand for Walls)?
The Brick Calculator tells you how many bricks you need for a wall, plus the cement bags and sand for the mortar that holds them together. Enter the wall's length and height in feet, choose a thickness (4.5" half-brick partition, 9" one-brick wall or 13.5" one-and-a-half-brick wall), subtract any door and window openings, and pick a mortar mix. The result includes a wastage allowance and shows every formula, so you can check it against your contractor's (thekedar's) count.
Bricks in Pakistan are sold as 9 × 4.5 × 3 inches. That is the size wall thicknesses are planned around: a 9" wall is one brick length thick, and a 4.5" wall is one brick width thick. Kiln bricks in practice usually come out slightly smaller, about 8.75 × 4.25 × 2.75 inches, and official tests have repeatedly found bricks below the regulated size. With a 3/8" (about 10 mm) mortar joint, each brick and its share of mortar takes up about 9.125 × 4.625 × 3.125 inches, or about 13.1 bricks per cubic foot of masonry. That is close to the rule of thumb of 13.5 bricks per cft used on Pakistani sites. You can change the brick size and joint to match the bricks you're buying.
The method: wall volume = (length × height − openings) × thickness. Bricks = wall volume ÷ volume of one brick with mortar, then wastage is added (5% is typical for breakage and cutting). Wet mortar = wall volume − volume of the bricks themselves. Because sand bulks and voids fill when water is added, the dry materials needed are about 1.33 × the wet volume. Cement = dry volume ÷ (1 + sand parts), converted to bags at about 1.25 cft per 50 kg bag. Sand = dry volume × sand parts ÷ (1 + sand parts).
Worked example: a 20 ft long, 10 ft high, 9" thick wall with no openings has a volume of 20 × 10 × 0.75 = 150 cft. At 13.1 bricks per cft that is about 1,965 bricks, or 2,064 with 5% wastage. The wet mortar is about 33.7 cft, so the dry volume is about 44.8 cft. In a 1:6 mix that needs about 6.4 cft of cement (5.12 bags, so buy 6) and 38.4 cft of sand. In a stronger 1:4 mix, cement rises to about 7.17 bags (buy 8) and sand falls to 35.8 cft.
Use 1:4 mortar for load-bearing walls, foundations below plinth level and walls exposed to damp, and 1:6 for ordinary internal and boundary walls. The calculator covers masonry only. Plaster is extra: roughly 1/2" on each face, which needs its own cement and sand. For a whole-house budget, including steel and concrete, use our House Construction Cost Calculator.
How to Use This Calculator
- 1Enter the wall length and height in feet. For several walls, add their lengths together if they share the same height and thickness.
- 2Choose the wall thickness: 4.5", 9" or 13.5".
- 3Enter the total area of door and window openings in sq ft (for example, a 3 × 7 ft door is 21 sq ft).
- 4Check the brick size and mortar joint. The defaults match typical Pakistani kiln bricks with a 3/8" joint.
- 5Pick the mortar ratio (1:4 or 1:6) and a wastage percentage.
- 6Read the bricks, cement bags and sand, add local prices for a cost estimate if you like, and copy the share link.