The process of impedance matching in electronic circuits is an important one. Thee are several accepted ways of do this and many of these techniques have been implemented in circuit simulators. However, failing the access to an advanced circuit simulator, javascript based calculators are a useful aid to the process of understanding reflection coefficients, return loss, VSWR, Smith Charts, transmission lines, etc. Signal Processing Group Inc., has released a set of calculators available online for interested users. These calculators are part of a recent book on VSWR and impedance matching but can be accessed independently of the book itself. Please access the calculators at http://www.signalpro.biz/impmatch.html.