We describe a web-based cgi calculator for constructing synthetic color-magnitude diagrams for a simple stellar population (SSP) using the Yonsei-Yale (YY) isochrone data base. This calculator is designed to be used interactively. It creates quick lo
ok CMD displays in (B-V) and (V-I) colors. Stochastic effects on the CMDs are included. Output in tabular form is also provided for special purpose displays, or for combining the CMDs of different stellar populations. This research tool has applications in studies of the stellar content of our Galaxy and external systems. It provides an easy way to interpret the CMDs in resolved stellar populations. It offers the means to explore the dependence of the integrated properties of unresolved stellar systems on stellar parameters (ages, chemical composition, binarity) and on the characteristics of their parent population (IMF slope and mass range).
