About Bulk Material Calculator

Bulk Material Calculator is a set of free calculators for estimating bulk landscape and construction materials — gravel, concrete, mulch, sand, topsoil, crushed stone and pavers. Give it the size of the area you are filling and it returns the volume in cubic yards, cubic feet and cubic metres, the weight in tons, bag counts where they apply, and the amount to order once a settling allowance is added.

It exists because the calculators already out there tend to do one material, hide the assumptions, and never show you the measurements they are working from. This one draws the area to scale as you type, so a wrong unit or a transposed number is easy to catch, and it puts volume and weight side by side so you can match whichever one your supplier quoted.

How the numbers are worked out

Every estimate is area × depth ÷ 27 for cubic yards, then multiplied by a typical density for weight and divided by a bag yield for bag counts. The densities are mid-range figures from ASTM C29 bulk-density data, ready-mix industry figures, published Quikrete and Sakrete bag yields, and landscape-supplier delivered-density tables, cross-checked against each other. The how we calculate page sets out every formula, every density, and the full source list.

Because bulk material varies ±10–15% with moisture and compaction, the results are estimates and the tool defaults to ordering 10% extra. Figures were last reviewed on 2026-09-07 and are rechecked whenever a reader reports a discrepancy.

Who builds it

The site is built and maintained by Madhu Kinnera, operating as Marava Tech. It is funded by advertising so the calculators can stay free — there is no sign-in, no paywall, and no subscription.

Every calculation runs in your browser. Nothing you type is sent anywhere or stored, and the tools work on a phone with a weak signal at the store or the job site.

Contact

Corrections and feedback are welcome — email hello@bulkmaterialcalculator.com. If a figure looks wrong, tell us the inputs you used and the number you expected, and we will check it against the sources.