Website computes matching probabilities for capillary electrophoresis autosomal STR profiles. Uses high-quality cosmopolitan population datasets. Queries limited to STRidER allele frequency data. Select country, continent, or entire database. Minimum input is one locus. Commercial kits limit displayed loci. Loci without data are dimmed. Only plausible allele values accepted. Invalid alleles cause false or biased results. Allele nomenclature details provided.