In this work, we present a simple pseudolinear function to extrapolate second virial coefficients to high temperatures or to correlate them using a Boyle temperature function. Accurate values of the Boyle temperature also result from this function if they arc not available from measurement. With the new function, only two experimental points are necessary to predict the second virial coefficient within experimental error over a wide range of temperatures. The new approach is valid for pure and mixture second virial coefficients. and it provides a means to check the internal consistency among data using the Boyle temperature as a reducing parameter. Also, it allows simple representations of the second virial coefficient from pair potentials. It can he considered a tool to cheek the correct behavior of equations of state.