Calculation of chromatographic dead times and retention indices with the aid of a computer program in BASIC. 
A computer program is presented for calculating chromatographic dead time from the observed retention times of an homologous series of standards using the iterative approximation procedure of Guardino et al.  The program is written in BASIC and is readily adaptable to most microcomputers capable of using BASIC.  Corrected retention times and capacity factors of standards and of samples are also calculated by the program.  Examples of applications in gas chromatography and reversed-phase high-pressure liquid chromatography are presented.  A listing of the BASIC program is given.