Voynex calculator is a Web browser application designed to evaluate mathematical and JavaScript expressions. The main difference between it and other calculators is that it is possible to enter the whole expression at once instead of entering it step by step. For example, it can evaluate expressions like, "sin(sqrt(PI/3)+sqrt(PI/5))+cos(PI/2+1)", "x=pow(4,5)+3; 3*x+log(x)", or "0xff07+0x1c04*(0x45+0x55>>1)". The power of the JavaScript language itself is used to evaluate expressions of arbitrary complexity. It offers a wide set of mathematical functions to calculate trigonometrical, logarithmic, and other expressions.