Planning a brick wall and not sure how many bricks to order? This brick calculator works out the exact number you need based on your wall size, brick dimensions, and mortar joint, then breaks the mortar down into cement and sand so you don’t run short mid-build or over-order and waste money.

Pick a wall type, choose a standard brick size or enter your own, and the numbers update as you type.

Why people use this tool

• No more guessing on brick orders: get an exact brick count, including a wastage buffer, before you go to the yard.
• Works with any brick size: choose Modular, UK, or US standard sizes, or enter custom dimensions for local or reclaimed bricks.
• Handles single and double walls: half-brick (single leaf) and full-brick (double leaf) construction are both supported.
• Accounts for openings: subtract the area of doors and windows so you’re not buying bricks for space you won’t fill.
• Cost estimate included: enter your local prices and see a full cost breakdown for bricks, cement, and sand.

How brick count actually works

A brick wall isn’t just wall area divided by brick size. Every course of bricks has a mortar joint running around it, and that joint adds real size to what’s actually being tiled. A standard 190×90mm modular brick with a 10mm joint effectively takes up a 200×100mm footprint on the wall face, not 190×90mm. Ignore the joint over a whole wall and you can undercount bricks by 10% or more.

The same idea applies in imperial: an 8×2¼in US Standard brick with a 3/8in joint effectively takes up an 8⅜×2⅝in footprint. Switch between Metric and Imperial in the calculator above and the brick count stays accurate either way.

This calculator adds the joint thickness to both the brick’s length and height before dividing it into your net wall area (wall area minus any door and window openings), then rounds up and adds your chosen wastage allowance on top for breakage and cuts.

Single vs double brick walls

A single (half-brick) wall is one brick deep, typically used for garden walls, partition walls, or the outer skin of a cavity wall. A double (full-brick) wall is two brick thicknesses laid side by side, giving a stronger, thicker wall commonly used for load-bearing exterior walls. Switching between the two in the calculator doubles both the brick count and the mortar needed, since it’s effectively two single-leaf walls built together.

Choosing a brick size

Brick dimensions vary by country and manufacturer. The calculator includes three common presets: Modular / Indian bricks at 190×90×90mm, widely used across Europe, Africa, and South Asia; UK Standard bricks at 215×102.5×65mm; and US Standard bricks at roughly 203×92×57mm (8×3⅝×2¼ inches). If your supplier uses a different size, or you’re working with reclaimed or antique bricks, switch to Custom and enter the exact length, depth, and height.

Mortar: the 1.33 dry-volume factor

Once the calculator knows how many bricks fit in the wall, it works out how much space is left for mortar: the total wall volume minus the solid volume of the bricks themselves. That’s the wet mortar volume. But cement and sand, as dry ingredients, take up more room than the compacted mortar they become once mixed and packed into a joint, so the calculator applies a standard 1.33 dry-volume factor to convert that wet volume into the raw material volume you need to buy.

From there, the mortar mix ratio (1:3, 1:4, 1:5, or 1:6, cement to sand) splits that dry volume into cement bags and sand, using the same 1,440 kg/m³ and 1,600 kg/m³ densities used across our other construction calculators.

Estimating cost

Toggle Estimate Cost and enter what you pay per brick, per bag of cement, and per cubic metre (or cubic yard) of sand. The tool multiplies each by the quantities calculated above and shows a line-by-line breakdown next to the total, so you know exactly how much of the budget goes to bricks versus mortar.

If you’re also pouring a footing or slab for the wall, the Concrete Calculator handles that separately. For unit conversions on a supplier quote, try the Volume Converter or Weight Converter. To work out the wall’s area before you get to brick counts, the Area Calculator is a quick first step, and the Percentage Calculator is handy for working out a custom wastage margin by hand.

These figures are for planning purposes. For load-bearing or structural brickwork, confirm quantities and specifications with a licensed contractor or engineer.