Home & Construction Calculators
Estimate concrete volume and a complete project budget, including ready-mix, short-load fees, delivery, labor, forms, reinforcement, equipment and tax.
Concrete cost formula
The calculator converts every dimension to feet before calculating area and volume. This prevents the common mistake of mixing feet, inches, meters and centimeters.
Net volume = area × depth
Order volume = net volume × (1 + allowance ÷ 100)
Total = material + fees + labor + forms + reinforcement + equipment + tax
There are 27 cubic feet in one cubic yard and 35.3147 cubic feet in one cubic meter. Ready-mix concrete is normally quoted by the cubic yard in the United States.
What the estimate includes
Material cost uses the adjusted order volume rather than the net volume. Labor and formwork are calculated from plan area. Short-load, delivery, reinforcement and pump costs are entered separately so you can match a real quotation instead of relying on a hidden average.
Worked example
A 20 ft × 10 ft slab at 4 in thick covers 200 ft² and contains 66.67 ft³, or 2.47 yd³, before allowance. With 10% extra, order volume is about 2.72 yd³. At $145 per yd³, concrete is about $394 before supplier fees. Adding the sample labor, forms, reinforcement, equipment and 5% tax produces a transparent project estimate.
Cost planning checklist
- Ask whether the supplier bills exact volume or rounds to the next increment.
- Confirm minimum-load, waiting-time and distance surcharges.
- Include base preparation, vapor barrier and finishing when applicable.
- Budget separately for demolition, permits and difficult access.
- Measure each slab, footing or pad separately when thickness changes.
Manual calculation steps
- Convert depth to feet and calculate cubic feet.
- Multiply by the number of identical sections.
- Add the selected waste or contingency allowance.
- Divide cubic feet by 27 for cubic yards.
- Multiply yards by the supplier price and add concrete delivery fees.
- Add area-based labor and forms, then fixed project costs and tax.
Choosing an allowance
Five to ten percent is common for simple preliminary planning, but irregular excavation, uneven subgrade, spillage and over-excavation can require more. An allowance is not a substitute for accurate measurement.
Frequently asked questions
What is a short-load charge?
It is a supplier surcharge for orders below the economical capacity of a ready-mix truck. Policies vary, so enter the quoted fee.
Should I round up cubic yards?
Use the adjusted result when requesting a quote, then follow the supplier ordering increment. Do not round the net volume before adding allowance.
Does the result include excavation and base gravel?
Only costs entered in the fields are included. Add separate estimates for excavation, subbase, permits, demolition, curing and specialty finishes.
Can I use metric measurements?
Yes. Select meters or centimeters for plan dimensions and depth. Results include cubic feet, cubic yards and cubic meters.
Common mistakes
- Entering a 4-inch depth as 4 feet.
- Forgetting multiple pads or thickened edges.
- Ignoring minimum-load and pump charges.
- Using an old material price or excluding sales tax.