Calc98 is a pocket calculator simulator program for the Microsoft Windows operating system. It is a replacement for the calculator program that is included with the operating system, with many additional features and greater flexibility. It is especially designed for scientific and engineering use and includes a wide range of units conversions and scientific functions. It also has statistics and financial and time functions, including a stopwatch.

This new version introduces improved user customization features, including the ability to install Calc98 to the system tray. It also offers better matrices and arrays, new display modes, more data (including a built-in periodic table of the elements), and better numerics.