How concrete is measured and ordered
Concrete is sold by volume, and in the United States the unit is the cubic yard: a cube three feet on each side, or 27 cubic feet. For a flat, rectangular pour the volume is simply the area times the depth, so the only trick is keeping units consistent. Length and width are usually in feet, but thickness is usually in inches, which means converting inches to feet by dividing by 12 before multiplying.
Add a margin on top of the geometric volume. Subgrades settle, forms bow slightly, and some concrete stays behind in the truck chute and the wheelbarrow. A waste allowance covers those losses so you are not left a few feet short when the pour is half finished, which is far more expensive than ordering a little too much.
What shapes the price of a concrete project
Concrete itself is only part of the bill, and the part that varies the most is rarely the volume. Expect these factors to move the total:
- Location and supplier. Ready-mix is a local business, so the same mix can be priced very differently from one plant to the next.
- Mix design. Strength rating, additives, fibers and color all change the price per yard.
- Delivery and order size. Many suppliers have a minimum load and charge extra for small orders, long distances or extended time on site.
- Site preparation. Excavation, a compacted gravel base, forms and drainage often cost as much as the concrete.
- Reinforcement and finish. Rebar or mesh, control joints, broom or stamped finishes, sealers and curing all add materials and labor.
- Access. If a truck cannot reach the forms, you may need a pump or a lot of wheelbarrow labor.
- Permits and inspections. Requirements depend on your city or county and on the type of work.
Before you call a supplier
- Measure the area and decide on a thickness. Sketch irregular shapes as a few rectangles and add them up.
- Get your volume in cubic yards, with a waste allowance, from the Concrete Cost Calculator.
- Ask two or three local ready-mix suppliers for the price per cubic yard for the strength you need, and what is on top: delivery, fuel, short-load, extra-time or weekend fees.
- Ask whether they have a minimum order, how long the truck can wait, and what happens if you need a partial extra load.
- Separately, price the preparation, forming, reinforcement, finishing and any permit. Add them to your budget.
When a calculator is not enough
A slab-on-grade estimate is a good starting point for a patio, a shed pad or a walkway. It is not a design. Footings, foundation walls, retaining walls, structural slabs and anything near a property line, utility or public right-of-way should be specified by a professional and checked against your local building code. Frost depth, soil conditions and loads all matter, and none of them can be judged from a few measurements.
Frequently asked questions
Does Home Metric Tools publish concrete prices?
Only as a clearly labeled reference. The cost calculator starts from an illustrative $180 per cubic yard, the ballpark of a published U.S. range of $160 to $195 per cubic yard (Concrete Network, updated July 14, 2026). It is not a local or real-time price and not a quote: concrete prices change by region, supplier, mix and order size, so replace it with the price from your supplier. See the source, date and limits.
Why is concrete measured in cubic yards?
Ready-mix suppliers in the United States quote and deliver concrete by the cubic yard, which is 27 cubic feet. Working in the same unit as the supplier makes your estimate directly comparable to a quote.
Should I order a little extra?
Most projects benefit from a margin, because forms are never perfect and the ground is rarely level. That is why the calculator includes an adjustable waste allowance. Your supplier or contractor can tell you what is sensible for your site.
Can I use these tools for a structural foundation?
Use them for a first quantity and budget check only. Footings, foundation walls and anything that carries load need design by a qualified professional and approval under your local building code.