A knowledge base and aggregator for human genomic variants. VarSome gives fast access to more than 33 billion items of variant and gene annotation sourced from public databases. It also provides advanced visualisations and features such as functinal annotation for any variant, known or unknown, as well as automated variant classification based on professional guidelines. Its tens of thousands of users add an fast-growing amount of their own insights on its pages. Users may also deploy the associated API to obtain data directly into their software.