RiC-O Converter is an open-source command-line tool to convert EAD finding aids and EAC-CPF authority records to RDF files conforming to Records in Contexts ontology, in a robust manner. It was developed for the Archives nationales of France (ANF) but is aimed to be reused by other archival institutions, and to this aim is fully documented in English. It is based on XSLT stylesheets that take into account the variability of EAD content. It enabled the ANF to convert 15000 EAC-CPF files and 29000 EAD files into an homogeneous knowledge graph. Such a graph opens new perspectives for navigating and linking from/to archival metadata.