SlabCalc

What is SlabCalc?

Free browser concrete calculator that returns volume in cubic yards and feet, bag counts for 40, 50, 60, and 80 pound bags, total weight, and installed cost for slabs, cylinders, curbs, stairs, columns, walls, footings, and tubes, in imperial or metric with an adjustable waste factor and no account

Vendor submission August 2026 from Christoph Wackher, who noted the cost methodology and its wide ranges without being asked. Cost figures quoted here are the vendor's disclosed range.

Key strengths

• Handles slabs, cylinders, curbs, stairs, columns, walls, footings, circles, and tubes
• returns volume, bag counts at four bag sizes, weight, and installed cost
• switches between imperial and metric with waste factors of none, 5, 10, or 15 percent
• publishes its cost methodology rather than presenting figures as quotes

Common use cases

Limitations to know

A single-purpose calculator rather than estimating or BIM software, which the vendor states directly. Cost figures come from state DOT paving bid records reprojected onto residential work through the BLS producer price index rather than from contractor quotes, so ranges are wide, for example $4.09 to $24 per square foot for driveways.