Terms

Estimates only

Every number this site produces is an estimate, built from figures this site sources and cites and dimensions you supply. It's a starting point for planning an order, not a guarantee of what you'll actually need or spend. Material densities, coverage rates, and waste all vary by supplier, by product, and by the specifics of your project in ways no calculator can fully account for — see the methodology page for how the figures behind these estimates are sourced.

Before placing a large or expensive order, confirm the relevant figure — density, coverage, sheet or box size — with your supplier or the product's own packaging. That confirmation is on you, not this site.

Not engineering or professional advice

These are estimating tools, not engineering software, and nothing here is professional advice. This site doesn't assess whether a design is structurally sound, whether soil will bear a load, or whether a plan will pass inspection — and, deliberately, it doesn't state numbers that codes and jurisdictions govern, like footing depth, slab thickness, joist spacing, or setbacks. Where one of those matters, this site names what determines it and points you to the authority — your local building department, your permit set, or a licensed engineer — rather than supplying a figure. Using a calculator here doesn't substitute for that.

No warranty, no liability

This site is provided as-is, with no warranty of any kind — including that any calculator is accurate, current, or fit for your particular project. I built this to be genuinely useful and I take the sourcing seriously, but I'm one person running a free tool, not a service you're paying for a guarantee on.

To the extent the law allows, I'm not liable for losses or damages arising from using this site or relying on its estimates — an over-order, an under-order, or a decision made on the strength of a number here. You're responsible for verifying anything you're about to spend real money on.

Content and sources

The writing, formulas, and site design here are mine. Where a figure is drawn from a supplier, manufacturer, trade authority, or government source, it's cited and linked rather than presented as this site's own claim — those sources own their own published data, and this site doesn't claim otherwise.

You're welcome to link to any page here. Reproducing the site's own text or design elsewhere without asking isn't.

Changes

Calculators, figures, and this page itself can change as sourcing improves or a mistake gets caught — see the about page for how corrections work. Continuing to use the site after a change means you accept the current version of these terms.

How the site handles data, analytics, and advertising cookies is covered separately on the privacy policy, not here.

Questions

If any of this is unclear, get in touch through the contact page.