About Us

Project Measure Lab publishes free browser-based tools for homeowners, contractors, estimators, and do-it-yourself planners in the United States. Our goal is to make common project math easier to check by showing the inputs, formula, assumptions, and limitations instead of presenting a result with no explanation.

How our calculators are built

Each calculator is designed around a specific planning question. Material tools convert measurements into quantities; electrical and HVAC tools use clearly stated engineering relationships; cost estimators use dated national planning ranges and identify the source used for the range. Calculations run in your browser and do not require an account or a database request.

What our tools are for

These tools are intended for early planning, comparison, budgeting, and checking your own arithmetic. They are not substitutes for a site measurement, a contractor quote, a permit review, a stamped design, or manufacturer instructions. Local codes, labor rates, waste factors, climate, material specifications, and job conditions can change the correct answer.

Editorial approach

We favor plain language, transparent formulas, useful examples, and conservative limitations. When a calculator uses a market cost assumption, we identify when that assumption was reviewed so visitors can judge whether it is suitable for their project. We also link related tools so a visitor can move from quantity planning to cost planning without repeating measurements unnecessarily.