Work out what to buy before you buy it.
Material calculators that show their working. Enter real dimensions, get quantities you can take to a supplier — and see exactly how each number was derived.
Open the Concrete Block CalculatorHow it works
- 01
Enter the wall
Length, height, and block size. Joint thickness, waste allowance, and grout spacing all have sensible defaults you can change.
- 02
Read the quantities
Blocks, mortar bags, core-fill grout, and finished wall weight — recalculated on every keystroke, with no Calculate button to press.
- 03
Check the working
Every formula is shown and every constant is listed with the source it came from and the date it was checked.
Calculators
Estimate how many concrete blocks (CMU) and how much mortar a wall needs, from wall dimensions and block size.
Estimate what the blocks for a concrete block wall cost, from a dated and sourced national price band, with mortar and grout counted but not priced.
Work out the concrete a slab, footing, round pier, post-hole or set of steps needs — volume in cubic yards and cubic feet, 40/60/80 lb bag counts, and the ready-mix order.
Estimate what a concrete slab, driveway, patio or footing costs to pour — concrete per cubic yard, labour per square foot, gravel base, reinforcement and delivery fees, itemised from dated, sourced price bands.
Work out how many rebar sticks a slab, driveway, wall, footing or column/beam needs — in-place length, purchase length and weight — plus a lap-splice length check against the ACI 318 code floor.
Estimate what rebar costs by the linear foot, from a dated national price band for black or galvanized bar, with a same-size per-pound and per-ton conversion for four common sizes.
Where the numbers come from
Block dimensions, mortar coverage, grout volumes, and wall weights are taken from manufacturer data sheets and published industry tables, not from rules of thumb. Each one is listed on the calculator page with its source and the date it was checked, so you can verify a figure rather than take it on trust. Where a value is derived rather than published, it says so.
Read the methodology