Disclaimer

Last updated: 2026-10-09

Estimates, not guarantees

The calculators and guides on Free Concrete Calculator produce estimates for planning and ordering. Actual quantities depend on things no calculator can see: forms that bulge, bases that are not level, over-excavation, compaction of aggregates, moisture in materials, spillage and the material left in trucks and tools. That is why most calculators add a waste allowance, and why you should round up when you order.

Not professional advice

Nothing on this site is engineering, architectural, legal or other professional advice. Calculating the volume of a footing, foundation, retaining wall, column or suspended slab is not the same as designing one. Sizes, reinforcement, concrete strength and depth for structural work must follow your plans, your local building code and, where required, a licensed engineer. Building permits and inspections may be required; check with your local building department.

Material data

Bag yields, strengths and coverage figures come from manufacturers' published data sheets. Material densities for gravel, stone, soil, sand and mulch are typical values; real material can differ by 10–15% or more with moisture and grading. Always use the figure from your own supplier or product label when it differs from ours. Our methodology page lists every assumption.

Prices

We do not publish prices as facts. Cost calculators multiply the prices you enter; the results are only as accurate as those inputs. Prices vary by region, season, mix, order size and delivery conditions. Get written quotes before committing to a project.

Safety

Wet concrete and cement are caustic and can cause skin burns and eye damage. Wear gloves, eye protection and long sleeves, and follow the safety instructions on the product. Heavy materials and machinery carry risk of injury; work within your ability and hire professionals when in doubt.

Brands and independence

Brand names such as QUIKRETE and Sakrete are trademarks of their owners and are used only to identify products and their published data. We are not affiliated with, sponsored by or endorsed by any manufacturer, retailer or supplier mentioned on the site.

Advertising

The site is supported by advertising, which may be served by Google and its partners. We do not control which ads appear, and showing an ad is not an endorsement. We do not currently use affiliate links; if we ever do, we will label them clearly.

Illustrations

Illustrations on this site are AI-generated artwork created to show typical jobs and materials. They are not photographs of real projects or products and are not to scale.

Limitation of liability

By using the site you accept that we are not liable for decisions you make based on its results, including material orders, costs, delays or damage. See our terms & conditions for the full terms.

Questions

If something looks wrong, please tell us or email hello@freeconcretecalculator.com.