RWebLogo is a wrapper for the WebLogo python package that allows generating of customised sequence logos. Sequence logos are graphical representations of the sequence conservation of nucleotides (in a strand of DNA/RNA) or amino acids (in protein sequences). Each logo consists of stacks of symbols, one stack for each position in the sequence. The overall height of the stack indicates the sequence conservation at that position, while the height of symbols within the stack indicates the relative frequency of each amino or nucleic acid at that position. In general, a sequence logo provides a richer and more precise description of, for example, a binding site, than would a consensus sequence.