NUMBRIV / 2026-10-31

Built for a clearer estimate

ContractorCostLab is a free collection of construction quantity and business calculators published by Numbriv. The launch editions cover the United States, Canada in English and French, the United Kingdom, and European English starting with Ireland.

Practical tools, open workings

The toolkit covers concrete, masonry, boards, paint, flooring, roofing, labour, pricing, equipment and cash flow. Each tool shows the formula, an example, assumptions and common mistakes. Values are editable planning scenarios, not industry benchmarks or supplier quotes.

Regional context without hidden assumptions

Region selection chooses language, currency formatting and initial units. It never converts currencies or certifies a local tax rate. Tax and cost inputs must come from your own project records. European English uses Ireland and EUR as its starting context; it does not represent a single rulebook for Europe.

Corrections and ownership

Numbriv maintains the software and educational content. Automated tests check selected formulas, conversions and interface flows; they do not constitute professional certification. Send a correction with the page address, non-confidential example inputs and the reason you believe the result should differ.

Questions or corrections?

Published by Numbriv. Questions, corrections and privacy requests: info@numbriv.com.

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