About Concrete Calculators

Concrete Calculators is a set of free estimating tools for people who pour concrete: contractors pricing a job on the tailgate and homeowners checking whether a quote is in the right zip code. It is built and maintained by the Concrete Calculators Editorial Team.

We are not a concrete contractor and we are not engineers, and the site never pretends otherwise. What we do is math, carefully.

Where the formulas come from

Every calculator runs on published industry figures rather than numbers we made up.

• Volume math is geometry: a cubic yard is 27 cubic feet, and a cubic meter is 1.30795 cubic yards.
• Bag yields come from the manufacturer coverage figures printed on the bags: 0.60 cubic feet for an 80 lb bag, 0.45 for a 60 lb bag, and so on.
• Block, mortar and sand factors follow the standard masonry rules of thumb used across the trade: 1.125 standard blocks per square foot of wall, one 80 lb mortar bag per 33 blocks, one cubic yard of sand per 1,000 blocks.
• Material weights and mix proportions follow figures published by the Portland Cement Association and the ready mix industry, such as 150 pounds per cubic foot for normal weight concrete.
• Every calculator page shows its formula in words with a worked example, so you can check our arithmetic by hand. We think you should.

How prices are set and reviewed

Cost calculators use stated defaults: $165 per cubic yard for ready mix, $45 per cubic yard for crushed stone, $4.50 per square foot for form, pour and broom finish labor, and the finish adders listed on each tool.

They are national planning figures, reviewed quarterly against plant price lists and trade surveys, and every one is editable right in the calculator so you can drop in your local quote. Cost results show a range of 12 percent under to 18 percent over the point estimate, because that is roughly how far honest quotes spread.

What these estimates are for

They are for planning: sizing an order, sanity checking a bid, deciding between bags and a truck. They are not engineering. Slab thickness, reinforcement, soil bearing and frost protection on anything structural belong to your local building department and, where loads matter, a licensed engineer. When a calculator's assumptions matter to the result, the page says so in plain words.

The methodology page lists every published figure and every editable assumption side by side, with the date each was last reviewed. Spot a number that looks stale or wrong? Corrections ship fast, because the whole point of this site is numbers you can trust. The editor's profile explains how every figure is sourced and reviewed.