Slabs | Footings | Circular columns | Concrete Calculator-how many bags or volume of concrete do you need Admin 26 Jul, 2020 Slabs Concrete Calculator Thickness inches Width feet Length feet Cubic Yards How many Pre-Mix Concrete Bags 40# Bags: 60# Bags: 80# Bags: Footing Concrete Calculator Depth inches Width inches Length feet Cubic Yards How many Pre-Mix Concrete Bags 40# Bags: 60# Bags: 80# Bags: Column Concrete Calculator Diameter inches Height inches Cubic Yards How many Pre-Mix Concrete Bags 40# Bags: 60# Bags: 80# Bags: