The Pro QC AQL (Acceptance Quality Limit) calculator (based on based upon ANSI Z1.4-2003) makes it easy to determine a sample size and the proper number of allowable rejects in a particular shipping lot size. It is a fundamental tool for preparing a sampling plan for a random product inspection as it allows to set the number of samples to inspect, and the maximum numbers of defects that is allowed. This free application takes the place of the traditional paper card that many inspectors in the field use.