Concrete Calculator
Estimate concrete volume, cubic yards, bags, weight and material cost for slabs, footings, walls, columns and stairs.
Concrete Calculator
Calculate concrete volume, cubic yards, bags, weight and estimated cost for common projects.
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How Much Concrete Do I Need? — Concrete Volume Calculator
Our concrete volume calculator helps you estimate how much concrete you may need for a slab, pad, footing, column, wall or set of stairs. Enter your measurements and the calculator will show the estimated volume in cubic feet, cubic yards and cubic meters.
You can also add extra material, choose a concrete density, estimate the number of concrete bags and calculate an optional material cost.
How the concrete calculator works
The basic calculation starts with the dimensions of your project:
- Rectangular slab or pad: length × width × thickness
- Circular slab or pad: π × radius² × thickness
- Footing: length × width × depth × number of footings
- Round column or footing: π × radius² × height × number of columns
- Wall: length × height × thickness
- Stairs: the calculator sums the volume of the individual steps
The calculator converts your measurements into a common volume and then applies the optional extra-material percentage. Weight is estimated from the volume and the concrete density selected.
Concrete calculator for common projects
The same tool can be used for several common concrete estimating needs. Use the slab or pad option for a concrete slab cost calculator estimate, the footing option as a concrete footing calculator, the round option for a concrete column calculator, the wall option for a concrete wall calculator, and the stairs option for a concrete stairs calculator.
These project types are included in the main calculator, so you do not need a separate tool for each shape. Choose the project type that matches your work and enter the measurements.
Concrete slab cost calculator
If you are planning a concrete slab, use this concrete slab cost calculator to enter the slab length, width and thickness. You can then choose a price per cubic yard to estimate the material cost.
For example, a 20-foot by 20-foot slab that is 4 inches thick has a base volume of about 133.33 cubic feet, or about 4.94 cubic yards. If you add 10% extra material, the adjusted volume is about 5.43 cubic yards. Your actual cost depends on the price you enter and the supplier’s pricing.
Concrete Cost Calculator
This concrete cost calculator can estimate material cost using either a price per cubic yard or a price per bag when a bag estimate is enabled. These are material estimates only and may not include delivery, labor, pumping, taxes, site preparation or other project costs.
For a supplier quote, use the calculator as a quantity check and compare the result with the supplier’s quoted quantity, product specifications and current price.
Concrete bags calculator
The calculator can also work as a concrete bags calculator when you are buying bagged concrete. Enable the bag estimate, choose the bag size and enter your project dimensions. The calculator uses an estimated yield for the selected bag size and rounds the required number of bags up to a whole bag.
Bag yields vary between products. Always check the yield printed on the specific product packaging before buying material.
Concrete Footing Calculator, Wall Calculator, Column Calculator and Stairs Calculator
The same concrete calculator can estimate several common project types. Use the concrete footing calculator option for footings, the concrete wall calculator option for walls, the concrete column calculator option for round columns or footings, and the concrete stairs calculator option for steps. Choose the project type that matches your shape and enter the required dimensions.
What concrete density should I use?
If you do not know the density, the calculator uses an average assumption for a general estimate. If your supplier or product documentation provides a density in pounds per cubic foot, choose Custom density and enter that value.
Density affects the estimated weight, but it does not change the volume calculation.
Should I add extra concrete?
Extra material is optional and starts at 0%. You can enter an additional percentage when you want to allow for project-specific conditions such as uneven surfaces, measurement differences, small losses or other material needs.
The right allowance depends on your project and how accurately the forms and measurements can be prepared. For important pours, confirm the required quantity with your contractor or concrete supplier.
Concrete calculator accuracy
The volume result is based on the measurements you enter. Weight, bag counts and cost are estimates based on the assumptions and product information selected in the calculator.
Actual concrete requirements can differ because of form dimensions, uneven subgrades, product yield, mix characteristics, waste, delivery requirements and supplier specifications. Use the calculator as a planning estimate rather than a guaranteed order quantity.
Frequently asked questions
How do I calculate how much concrete I need?
Multiply the project’s length by its width and thickness for a rectangular slab or pad. For other shapes, use the matching project type in the calculator. The calculator handles the unit conversions for you.
Can I use this as a concrete slab cost calculator?
Yes. Select the rectangular slab or pad option, enter the slab length, width and thickness, and enter a price per cubic yard if you want a material cost estimate.
Can I use this as a concrete footing calculator?
Yes. Select the footing option and enter the footing dimensions and quantity. The calculator estimates the total concrete volume for the footings.
Can I calculate concrete for walls, columns and stairs?
Yes. The main calculator includes separate options for walls, round columns or footings, and stairs. This means you can use it as a concrete wall calculator, concrete column calculator or concrete stairs calculator without using a separate tool.
How many cubic yards of concrete do I need?
Enter your project dimensions and thickness. The calculator converts the resulting volume into cubic yards so you can compare the estimate with supplier pricing or ordering requirements.
How many bags of concrete do I need?
Enable the bag estimate, choose the bag size and enter your project dimensions. The calculator estimates the number of bags using the selected product-yield assumption and rounds the result up to a whole bag.
Can I calculate concrete cost?
Yes. Enter a price per cubic yard or, when using bag estimates, a price per bag. The calculator will show an estimated material cost.
Is the concrete weight exact?
No. Weight is an estimate based on the concrete density selected. Actual density can vary by mix and product, so use supplier information when available.
Can this concrete calculator estimate a slab cost?
Yes. Enter the slab dimensions, choose any extra material allowance, and enter a price per cubic yard to get an estimated material cost. The result does not include labor, delivery or other project charges.
Can I use this as a concrete volume calculator?
Yes. The calculator converts your project dimensions into cubic feet, cubic yards and cubic meters. It supports slabs, pads, footings, columns, walls and stairs.
Can I use this as a concrete footing calculator?
Yes. Select the footing option and enter the footing dimensions and quantity. The calculator estimates the total concrete volume and can also estimate weight, bags and material cost.
Can I use this as a concrete wall calculator?
Yes. Select the wall option and enter the wall length, height and thickness. The calculator estimates the concrete volume and related material quantities.
Can I use this as a concrete column calculator?
Yes. Select the round column or footing option and enter the radius, height and number of columns. The calculator estimates the total concrete volume.
Can I use this as a concrete stairs calculator?
Yes. Select stairs and enter the step dimensions and number of steps. The calculator estimates the combined concrete volume for the steps.
Does the calculator include delivery and labor?
No. The cost result is a material estimate based on the price you enter. Delivery, labor, pumping, site preparation, taxes and other charges may be separate.
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