ROBIN is a web server for analyzing genome rearrangement of block-interchanges between two chromosomal genomes. It takes two or more linear/circular chromosomes as its input, and computes the number of minimum block-interchange rearrangements between any two input chromosomes for transforming one chromosome into another and also determines an optimal scenario taking this number of rearrangements. The input can be either bacterial-size sequence data or landmark-order data. If the input is sequence data, ROBIN will automatically search for the identical landmarks that are the homologous/conserved regions shared by all the input sequences.