Free block and concrete calculator

Enter the size of the wall or slab in feet or metres. Get the blocks, concrete, cement, sand and stone to order. No sign-up needed.

Wall lengthftWall heightftDoors and windowssq ftAdd up the openings. A 3 ft x 7 ft door is 21 sq ft.Waste allowance%Block sizeFace size including the 10 mm mortar joint, so a 390 × 190 block is 400 × 200. Block thickness does not change the count.

Blocks to order: 189
Blocks before waste: 180
Net wall area: 160.0 sq ft
Blocks per sq ft: 1.125

Want it in Excel?

Leave your WhatsApp number or email and we will send you the Excel version, so you can save a sheet for each job.

The calculator is one of eight tools in the full kit. See what is in the kit.