Concrete Patio Calculator
Determine exact concrete yardage, bag counts, and gravel base for outdoor patios and walkways.
Enter Your Dimensions
US • ftHow We Calculated This
• Order ready-mix concrete for jobs over 1 cubic yard (equivalent to approx 45-50 bags).
• Ensure subgrade is compacted and forms are properly staked before pour.
Formula & Volumetric Method
Volume = Patio Length × Width × Thickness. Slope 1/4 inch per foot away from building foundations.
Calculations are performed strictly using standard civil engineering constants. Volumetric outputs are normalized to true compaction rates, ensuring purchased quantities match jobsite yields.
Jobsite Engineering Guidelines
- Maintain a 1/4 inch per foot slope away from house foundations to prevent standing water pooling against walls.
- 4 inches is the standard depth for pedestrian outdoor patios.
Frequently Asked Questions
How accurate is the Concrete Patio Calculator for ordering materials?
Our calculations match standard store packaging sizes in the US, Canada, UK, and Australia. We include a safety waste buffer (default 8% to 12%) so you do not run short due to uneven ground or spillage.
Why should I add extra for waste when ordering?
Uneven ground, cutting scrap, and leftover mix in the wheelbarrow or mixer drum consume an extra 5% to 15% of material. Ordering only the exact measurement usually leaves you short, which can lead to expensive extra delivery fees.
Does this calculator support both Imperial and Metric units?
Yes. You can switch between US Customary (feet, inches, cubic yards, pounds), Canadian units, UK metric, and Australian standards using the region selector in the header or the unit dropdown on each input.