About Concrete Footing Calculator

What Is This Tool?

Concrete Footing Calculator is a free online tool that helps you figure out exactly how much concrete you need for footings, post holes, and foundations. Enter your hole dimensions and the number of holes, and instantly see how many 60lb bags, 80lb bags, or cubic yards of ready-mix concrete to order — plus estimated costs.

Who Is It For?

Whether you're a homeowner building a deck or fence for the first time, or a contractor estimating materials for a client project, this calculator saves you time and helps you avoid buying too much or too little concrete.

Frost Line Lookup

The calculator includes a built-in frost line lookup by ZIP code. Enter your ZIP and instantly see the recommended minimum footing depth for your area — helping you meet local building codes and avoid frost heave damage.

Why Is It Free?

We believe everyone should have access to accurate building calculations without paywalls or sign-ups. The site is supported by advertising, which allows us to keep the tool free for everyone.

Accuracy

The calculator uses standard industry formulas and includes a 10% waste factor for bagged concrete to account for spillage and variations in hole shape. Ready-mix estimates are rounded up to the nearest quarter yard since that is the typical minimum increment for delivery orders. While these estimates are reliable for planning purposes, always verify requirements with your local building department.