Generating random percolation clusters. A FORTRAN-77 program generator.f is presented to generate random percolation clusters. Cluster sizes up to n = 500 pixels can be generated. Random numbers are generated using the Manly random number generator and clock time. A second FORTRAN-77 program cluster.f enables the identification of the different clusters out of a set of randomly generated clusters. Using cluster.f, the 63 possible different clusters for n = 5 are selected. The percolation clusters are generated and presented using a matrix approach.