It's a fast equation parser/evaluator with parse-tree builder and user-friendly interface for parsing and calculation a run-time defined math expression. The math expressions is represented as string in a function style F(x1, x2,..., xn) =f(x1, x2,..., xn) , where F(x1, x2,..., xn) - declares number and names of the variables; f(x1, x2,..., xn) - math expression may contain: -variables x1, x2,..., xn and numbers, -arithmetic operations + - * / ^, -supporting a large set of math functions: sqrt, sin, exp, cos, tan, ln, abs, acos, asin, atan, cosh, log10, sinh, tanh, -constants e= 2.71828182845904 and pi= 3.14159265358979, and -user defined functions and constants. For example: F(x, y) = 3*x^2+y^2+e/4, F(x1, x2, y) = (x1-sin(x2))/y, F()=5+6+pi. Algorithm, which is used here, has been developed and implemented by Easy Math Solution and has different binary (static link library, dynamic link library and COM) implementation and programming approach (procedural and object oriented). It allows using EquTranslator in C/C++, C#, Delphi, VB and other languages and systems that can understand dll and COM.