AllerCalc (formerly known as VersaCalc) is an expression calculator which allows you to directly enter an expression to be evaluated. This versatile calculator features a re-sizable rolling display storing all of your inputs and results. It also has more than one hundred functions, including algebraic, transcendental, trigonometric, hyperbolic, engineering, statistical, and financial functions.

Calculations are not only in decimal but also in binary, octal, hexadecimal, and other numeric bases. It also has a comprehensive unit converter that can convert between virtually any two units in metric, English, and US systems.