The Concrete Technician Calculator is a tool to aid the Concrete Field Technician in calculating the equations in ASTM C138 (unit weight, yield, relative yield, cement content & air content) which are required in performing daily inspections. Calculations can be determined in English or SI units. Also, a concrete calculator is provided to determine how much concrete is needed to complete a project or if you have a small project around the house you can take the guesswork out of determining how much concrete you will need. The app will determine how much concrete is required in yd3, ft3 and various sizes of sack concrete.