About BuildCalc

What BuildCalc Is

BuildCalc is a free collection of construction and renovation material calculators built for homeowners, DIYers, and small contractors in the United States. Whether you are pouring a patio, painting a bedroom, or flooring a basement, the goal is the same: give you a fast, reliable quantity estimate before you spend a dollar at the lumberyard or big-box store.

Every calculator is paired with plain-English explanations and measurement guides, so you are not just getting a number — you are learning how the number is built.

Transparent Formulas, No Black Boxes

We believe an estimate you cannot inspect is an estimate you cannot trust. Each calculator on BuildCalc shows the formula it uses, the assumptions behind it — coverage rates, bag yields, waste allowances — and worked examples you can check with a pencil. If you disagree with an assumption, you can adjust your inputs or allowances and see exactly how the result changes.

Our formulas follow common industry conventions: cubic feet divided by 27 for concrete yardage, 350–400 square feet per gallon for paint coverage, 10–15% waste factors for flooring, and so on. Where products vary, we say so and tell you to check the label.

Private by Design

BuildCalc is a purely client-side website. All calculations happen in your browser, on your device. Nothing you type into a calculator is uploaded, stored, or logged anywhere. There are no accounts, no sign-ups, and no paywalls — the tools are simply there when you need them.

The site is supported by advertising, which keeps every calculator free to use.

A Work in Progress

We add calculators and improve existing ones over time. If a formula looks wrong, a yield seems off, or there is a calculator you wish existed, we genuinely want to hear about it — real-world feedback from people mid-project is how the site gets better.

Photo Credits

The photography on this site comes from openly licensed Creative Commons collections (Wikimedia Commons and Flickr, via the Openverse catalog). We are grateful to the creators below for sharing their work.

Wood-framed house by Jaksmata, CC BY-SA 3.0 (creativecommons.org/licenses/by-sa/3.0), via Wikimedia Commons. Concrete pour by MTA C&D - East Side Access, CC BY 2.0, via Flickr. Indoor painting supplies by David Mulder, CC BY-SA 2.0, via Wikimedia Commons. Laminate installation by Lee J Haywood, CC BY-SA 2.0, via Flickr. Mulch Mania by terren in Virginia, CC BY 2.0, via Flickr. Gravel driveway base by sebilden, CC BY 2.0, via Flickr. Drywall installation by OlgerFallasPainting, CC BY-SA 2.0, via Flickr. Tile work by MrVJTod, CC BY-SA 2.0, via Flickr. Roof install by joncallas, CC BY 2.0, via Flickr. Measuring tapes by chimpwithcan, CC BY 2.0, via Flickr.

Contact

Reach us any time at hello@buildcalc.pages.dev. We read every message and typically reply within 2–3 business days.