Methodology

Who runs this site

groundmath.com is built and maintained by Cloudwards e.K. (owner: Oliver Sinz), a German sole proprietorship that also operates the real-estate calculator sitedealyield.app. Full operator details are in the legal notice.

Where the numbers come from

Every density, coverage rate, recommended depth, waste factor, and package size used by a calculator is cited to a verifiable publication — university extension services first (Purdue, Mississippi State, Virginia Cooperative Extension, and others), then government agencies and producer technical specifications. Each calculator page lists its sources with the date we last verified them. We do not publish numbers we cannot cite.

Material properties are ranges, not single numbers — topsoil density varies with moisture, pallet coverage varies by producer. Where sources give a range, we show the range, state which default the calculator computes with, and let you override it. Corrections that differ in kind are kept apart: cutting waste is added to the computed quantity as its own visible line, and compaction (for aggregates) is applied to depth — never silently baked into a single fudge factor.

Versioning and freshness

The dataset behind the calculators is versioned. Every calculator page shows its formula version and data version with a “verified” date, and every data change is recorded in a changelog with the exact supporting quotes from its sources. We re-verify published values against their sources at least annually; the verified date on each page tells you when that last happened.

What these calculators are not

Results are planning estimates for homeowners and contractors doing takeoffs — not engineering advice, and not a substitute for your supplier's product specifications or your local building code. Pages whose topics carry real stakes (retaining walls, fence post depth) say so prominently and tell you when to involve a professional.

Corrections

Found a number that looks wrong, a source that has moved, or a formula you disagree with? Emailhello@groundmath.com with the page URL. Confirmed errors are fixed in the dataset, the changelog records the correction, and the page's data version is bumped — the audit trail is never erased.