SlabFast is a free concrete calculator designed for homeowners, DIYers, and contractors who need fast, accurate estimates for concrete projects. Whether you're pouring a patio slab, setting fence posts, building footings, or filling columns, SlabFast gives you cubic yards, cubic feet, bag counts, and cost estimates instantly — no signup, no login, no fuss.
The calculator supports four common project shapes: rectangular slabs and footings, round columns and piers, and post holes with optional post deduction. It also includes an adjustable waste factor so you never come up short on the job site. All calculations follow standard industry formulas used by professional contractors, based on Quikrete and Sakrete manufacturer specifications and ACI guidelines.
SlabFast is completely free to use. No account required. Your measurements stay in your browser and are never sent to our servers. If you have questions or feedback, get in touch at contact@slabfast.com.