A COVID-19 virus mutation tracker system (CovMT; appendix) based on SARS-CoV-2 isolate genomes deposited to GISAID to track the worldwide sequencing efforts <span class="attribute-to-highlight medbox">and</span> the evolution of the mutational landscape of this virus. CovMT, which is updated daily, summarises mutations from more than 450 000 isolates into groups of generic virus clades, lineages, <span class="attribute-to-highlight medbox">and</span> more specific mutation sets we call mutation fingerprints.