About ContractorBuilds

ContractorBuilds publishes construction calculators that show their working. Every figure carries a label saying where it came from, and every reference check names the standard and edition it checked against.

The calculators run on one shared calculation engine, so the same input produces the same answer on the website and in the apps. The engine is tested against worked examples and against other published calculators, and where it disagrees with one, the reason is recorded rather than reconciled quietly.

Read more about how the numbers are made on the methodology page.