We all complain occasionally about Microsoft, but the advantage of their monopoly position is that everyone has the same programs. As a result, in spite of everything there is at least a sort of standardisation. The program described here runs under Excel and calculates the serial and parallel values of resistors and capacitors.You can enter up to four values in the input section, and the output section displays the both the calculated value and the result rounded to the nearest value in the E12 series.