A practical brick and mortar calculator that turns wall dimensions into a shopping list: the exact number of bricks, the mortar volume and bags, and a cost estimate. It is built for self-builders, bricklayers, landscapers and anyone pricing a garden wall, extension or single-skin partition before a trip to the builders’ merchant. Everything runs in your browser, so you can iterate on sizes and prices without anything being uploaded.
How it works
You start by choosing metric or imperial and a brick size. Common standards are built in — UK (215 × 65 × 102.5 mm), US modular and standard, Euro RF and Australian — or you can type a fully custom brick. Then you add each wall as a length and height, and optionally subtract openings such as doors and windows so you are not paying for bricks you will never lay.
The count comes from a simple, well-known rule: every brick takes up its own face plus one mortar joint along the length and one up the height. So the area one brick consumes on the wall face is (brickLength + joint) × (brickHeight + joint). Dividing one square metre by that area gives bricks per square metre — about 60 for a UK brick at a 10 mm joint. Multiply by the net wall area, then by the number of brick leaves (single, double or triple thickness), and add your wastage percentage for cuts and breakages.
Mortar is handled by volume rather than a rough per-brick guess. The tool computes the solid wall volume from net area times wall thickness, subtracts the volume the bricks themselves occupy, and treats the gap as mortar. It adds 10% for mixing and spillage waste, reports the result in litres and cubic units, and divides by your bag yield to give whole bags. Finally it multiplies bricks by your price per brick and bags by your price per bag for a clear cost estimate.
Formula note
Bricks per square metre and the mortar split follow industry-standard estimating maths. Joint thickness matters a lot: a 10 mm joint versus a 6 mm joint changes the brick count by several percent over a large wall, which is why the joint is an input rather than a fixed assumption.
Worked example
A single-skin garden wall is 5 m long and 1.8 m high, with no openings — a net area of 9 m². Using a UK brick at a 10 mm joint, that is about 60 bricks per square metre, so roughly 540 bricks before wastage. Add the default 10% wastage and you should buy about 594 bricks.
For the mortar, a half-brick wall is about 102.5 mm thick, giving a solid volume near 0.92 m³. After removing the brick solids and adding mixing waste, you need on the order of 0.2 m³ of mortar — several bags depending on your bag yield. Plug in your local prices to see the total cost, then round up to whole packs when you order.