Professional reference for the building trades · tradeconvert.pro · Concrete Calc V2.0

Concrete Calculator — Cubic Yards & Bag Estimator

Precisely calculate volume for slabs, footings, and columns. Estimate ready-mix truck loads or individual bags for smaller projects.

One cubic yard of concrete equals 27 cubic feet. For a standard 4-inch slab, one cubic yard covers approximately 81 square feet. If using 80lb bags, you need 45 bags to make one cubic yard.

Volume Estimator

Length × Width × Depth

Length (ft)

Width (ft)

Depth (in)

Calculated Results

Cubic Yards

1.23

60lb Bag

Cubic Meters

0.941

80lb Bag

Concrete Coverage Reference

Estimates based on nominal depth. Always order 10% extra for waste and spillage.
Slab Depth	Yards per 100 sq.ft	Sq.ft per Cubic Yard
4 Inches	1.23 yd³	81 ft²
5 Inches	1.54 yd³	65 ft²
6 Inches	1.85 yd³	54 ft²
8 Inches	2.47 yd³	40 ft²