Brick calculator — estimate a wall in seconds
A brick calculator turns a wall’s dimensions into the number of bricks you need to buy. Enter the length and height, pick a standard brick size (the presets already include a 10mm mortar joint), and add a waste allowance for breakage and offcuts.
How it works
The tool computes the wall area, then divides by the face area of one brick (width × height, mortar joint included):
wall area = length × height base bricks = wall area ÷ brick face area total = base bricks × (1 + waste% ÷ 100), rounded up
For the UK standard preset the face area is 0.225 × 0.075 = 0.016875 m², which is about 59 bricks per square metre.
Example
A 10 m × 2.4 m wall using UK standard bricks with a 10% waste allowance:
- Wall area = 10 × 2.4 = 24 m²
- Base bricks = 24 ÷ 0.016875 ≈ 1423 bricks
- With 10% waste ≈ 1565 bricks
| Wall area | Bricks/m² (UK std) | + 10% waste |
|---|---|---|
| 24 m² | ≈ 59 | ≈ 1565 |
This is a single-skin estimate. The result updates instantly in your browser, with nothing uploaded.
Brick types and face area
The tool uses two standard presets, each including a 10mm mortar joint in the face area:
| Preset | Brick size | Face including joint | Bricks/m² |
|---|---|---|---|
| UK standard | 215 × 65 mm | 225 × 75 mm | ~59 |
| US modular | 194 × 57 mm | 204 × 67 mm | ~73 |
These are the most widely used sizes in their respective markets, but regional and manufacturer variants exist. If you are using a non-standard brick, calculate the face area as (brick width + mortar joint) × (brick height + mortar joint) and use that figure to divide your wall area.
Choosing the right waste allowance
The standard 5–10% range covers typical straight-run walling. Increase the allowance when:
- The wall has many corners or openings. Each corner requires cut bricks; a window or door opening produces offcuts that usually cannot be reused on the same course.
- You are using soft handmade bricks that crack more easily than engineering bricks.
- The bond pattern involves many half-bats (English, Flemish, or header bond all require more cuts than running bond).
- You are ordering from multiple deliveries and need to allow for batch variation.
For a simple garden wall with few openings, 7.5% is a reasonable middle ground. For a complex facade with many windows, 12–15% is safer.
Single-skin versus double-skin walls
The estimate is for a single skin (half-brick, 102mm) wall. Most UK residential cavity walls have two skins with a 100mm cavity between them. For a full-cavity wall, double the brick count. For a full-brick (215mm) solid wall, also double the count. Internal partition walls (a single skin) and low garden walls are the most common single-skin applications.
Ordering tip
Bricks are typically sold by the pack (often 400–500 units on a pallet). Round up to the nearest full pack to avoid a costly small supplementary order if you run short. Running short mid-job with unmatched bricks from a different batch is one of the most common and frustrating masonry mistakes.