Calculators

Each one shows its formula, a worked example and the published figures it relies on, so you can check the answer yourself.

Concrete calculator

Cubic yards and 40/60/80 lb bags for slabs, footings and post holes.

Add rooms and odd shapes; get ft², m², yd² and acres.

Cubic yards and tons, with density by stone type.

Cubic yards or bags for lawns, beds and low spots.

Tiles, boxes, waste and an optional grout estimate.