The IEA’s IDB Analyzer is an application created by the IEA to facilitate processing and analyses of international large-scale assessment databases. Originally developed in 2004 to be used with IEA’s own data, it is currently configured to work with most international large-scale assessment databases, as well as a few national assessments. In this chapter we describe the main features and capabilities of the IEA’s IDB Analyzer and present an illustrative example of how to use the two modules that comprise the IEA’s IDB Analyzer. We present and describe an example output and provide a brief overview of the statistical techniques and procedures addressed by the application.