Free construction calculators

Measure twice. Buy once.

Concrete, paint, roofing, fencing and more. Type in your measurements, get the number you need, and get back to work.

Browse calculatorsNo sign up. No downloads.

Try it: concrete slab

live demo
ft
ft
in

You need

1.63 cubic yards

includes 10% waste

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Built to be checked

Material estimates go wrong in two ways: the formula is hidden, or the assumptions are. Each calculator here states both. You will see the exact arithmetic in the results notes, the standard allowances (like 21 square feet per door), and the waste factors, and you can change any assumption that does not match your project.

The defaults reflect common US materials and practices: 80 lb concrete bags, 350 square feet per gallon of paint, three shingle bundles per square. Prices and product sizes vary by region and brand, so treat every result as a strong starting point for your shopping list, then confirm against the packaging or your supplier before ordering.

The name is borrowed from the trades: a takeoff is the step where a builder counts every material a job needs before buying. These calculators do that step for you.