eCalc is a free Windows calculator with basic and scientific functions. The calculator is designed with a high level of aesthetics, including large buttons and an easy to read display. The calculator operates with a frameless border and stays open above your other programs - making it an ideal side companion tool. Notable features of this calculator include memory functions, percent, sqrt(x), sqr(x), inv(x), and an engineering exponent key (EEX). The calculator includes a link to eCalc's online scientific calculator which supports more advanced features such as unit conversion, trigonometric functions, equation solving, and complex number math.