# Brick Calculator

URL: https://speedycalculator.com/calculators/construction/brick/
Last updated: 2026-10-25

> The brick calculator estimates how many bricks a wall needs for seven common brick sizes, single or double thickness, minus doors and windows, plus the mortar volume, bags of mortar mix and the total cost.

## Inputs

- Wall length (ft, m, in, yd, cm)
- Wall height (ft, m, in, yd, cm)
- Doors and windows area (ft², m², yd², acre)
- Brick size
- Wall thickness
- Mortar joint (in, cm, mm, ft, m, mm)
- Waste (%)
- Price per brick (/piece)
- Price per bag of mortar mix (/piece)

## Results

- Net wall area
- Bricks per unit area
- Bricks needed
- Mortar volume
- Bags of mortar mix (80 lb / 36 kg)
- Total cost

## Formula

```
Bricks per m² = wythes ÷ ((L + joint) × (H + joint))
Bricks = net wall area × bricks per m² × (1 + waste)
Mortar = net area × wythes × [(L + j)(H + j) − L × H] × depth ÷ ((L + j)(H + j))
```

## Explanation

Brick sizes differ between countries and manufacturers, and the mortar joint (usually ⅜ in or 10 mm) adds a surprising amount to each brick's footprint. A modular brick wall needs about 6.75 bricks per square foot of single-skin wall; UK walls need about 60 bricks per square metre. Always subtract doors and windows and add 5–10% for breakage and cuts.

### How to use the Brick Calculator

- **Wall length**
- **Wall height**
- **Doors and windows area**
- **Brick size**
- **Wall thickness**
- **Mortar joint**
- **Waste**
- **Price per brick**
- **Price per bag of mortar mix**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Enter the wall length and height, the area of openings, choose the brick size and number of wythes (skins), the mortar joint and waste allowance. The calculator finds the bricks per unit area including joints, the bricks needed, the volume of mortar between them and the number of 80 lb (36 kg) bags of mortar mix.

### Bricks per area (single wythe)

BrickJointPer ft²Per m²Modular 7⅝ × 2¼ × 3⅝ in⅜ in / 10 mm6.8573.7Standard 8 × 2¼ × 3⅝ in⅜ in / 10 mm6.5570.5Queen 7⅝ × 2¾ × 3 in⅜ in / 10 mm5.7662.0King 9⅝ × 2⅝ × 3 in⅜ in / 10 mm4.8051.6Utility 11⅝ × 3⅝ × 3⅝ in⅜ in / 10 mm3.0032.3UK standard 215 × 65 × 102.5 mm⅜ in / 10 mm5.5559.8Metric (EU) 240 × 71 × 115 mm⅜ in / 10 mm4.6249.8

### Tips for an accurate estimate

- Sketch the job and split irregular areas into rectangles, circles and triangles before you measure.
- Add a waste allowance – typically 5–10% for simple layouts and 15–20% for diagonal, curved or heavily cut work.
- Check the coverage or yield printed on the product, because sizes and densities vary between manufacturers.
- Buy all units of a finished material (tile, brick, siding) from the same batch so colours match, and keep a few spares for repairs.
- Confirm local prices – quarry, lumber and steel prices vary widely by region and season.

### Common mistakes to avoid

- Ordering exactly the calculated amount with no allowance for breakage, offcuts and settlement.
- Forgetting to subtract doors, windows and other openings – or subtracting small ones that still need cutting around.
- Confusing US short tons (2,000 lb) with metric tonnes (1,000 kg) when comparing quotes.

### Inputs explained

FieldWhat to enterWall lengthUnits: ft, m, in, yd, cmWall heightUnits: ft, m, in, yd, cmDoors and windows areaUnits: ft², m², yd², acreBrick sizeChoose one: Modular 7⅝ × 2¼ × 3⅝ in, Standard 8 × 2¼ × 3⅝ in, Queen 7⅝ × 2¾ × 3 in, King 9⅝ × 2⅝ × 3 in …Wall thicknessChoose one: Single wythe (½ brick), Double wythe (1 brick)Mortar jointUnits: in, cm, mm, ft, m, mmWasteIn %Price per brickUnits: /piecePrice per bag of mortar mixUnits: /piece

### What each result means

- **Net wall area** = max([Wall length]×[Wall height] - [Doors and windows area], 0)
- **Bricks per unit area** = [Wall thickness]÷(([Brick length] + [Mortar joint])×([Brick height] + [Mortar joint]))
- **Bricks needed** = ceil([Net wall area]×[Bricks per unit area]×(1 + [Waste]÷100))
- **Mortar volume** = [Net wall area]×[Wall thickness]×(([Brick length] + [Mortar joint])×([Brick height] + [Mortar joint]) - [Brick length]×[Brick height])×[Brick depth]÷(([Brick length] + [Mortar joint])×([Brick height] + [Mortar joint]))×1.1
- **Bags of mortar mix (80 lb / 36 kg)** = ceil([Mortar volume]÷0.019)
- **Total cost** = [Bricks needed]×[Price per brick] + [Bags of mortar mix (80 lb ÷ 36 kg)]×[Price per bag of mortar mix]

## Worked example

Inputs — Wall length: 30 ft; Wall height: 8 ft; Doors and windows area: 21 ft²; Brick size: Modular 7⅝ × 2¼ × 3⅝ in; Wall thickness: Single wythe (½ brick); Mortar joint: 0.375 in; Waste: 5 %; Price per brick: $0.65 /piece; Price per bag of mortar mix: $8 /piece.

Results — Net wall area = 219 ft²; Bricks per unit area = 6.85 per ft²; **Bricks needed = 1,576**; Mortar volume = 13.32 ft³; Bags of mortar mix (80 lb / 36 kg) = 20; Total cost = $1,184.40.

## Key terms

- **Wythe**: One vertical layer of masonry, one brick thick.
- **Modular brick**: U.S. brick whose size plus a ⅜ in joint gives a 8 × 2⅔ in module (three courses = 8 in).

## FAQ

**How many bricks are in a square foot?**
About 6.75 modular bricks per ft² with ⅜ in joints (single wythe).

**How many bricks per square metre?**
About 60 UK-format bricks (215 × 65 mm) with 10 mm joints, or 120 for a one-brick-thick wall.

**How much mortar do I need?**
Roughly 7–8 ft³ per 1,000 modular bricks with ⅜ in joints – about one 80 lb bag of mortar mix per 50–60 bricks. Add more for wider joints or cavity fill.

**What waste should I add?**
5% for straightforward walls and 10% where there are many cuts, piers or corners.

**What formula does the Brick Calculator use?**
Bricks per m² = wythes ÷ ((L + joint) × (H + joint)).


## Sources

- [Brick Industry Association – Technical Note 10](https://www.gobrick.com/)