Massive amounts of 16S rRNA sequencing data have been stored inpublicly accessible databases, such as GOLD, SILVA, GreenGenes(GG), and the Ribosomal Database Project (RDP). Many of thesesequences are tagged with geo-locations. Nevertheless,researchers currently lack a user-friendly tool to analyzemicrobial distribution in a location-specific context. BioAtlasis an interactive web application that closes this gap betweensequence databases, taxonomy profiling and geo/body-locationinformation. It enables users to browse taxonomically annotatedsequences across (i) the world map, (ii) human body maps and(iii) user-defined maps. It further allows for (iv) uploading ofown sample data, which can be placed on existing maps to (v)browse the distribution of the associated taxonomies. Finally,BioAtlas enables users to (vi) contribute custom maps (e.g. forplants or animals) and to map taxonomies to pre-defined maplocations. In summary, BioAtlas facilitates map-supportedbrowsing of public 16S rRNA sequence data and analyses ofuser-provided sequences without requiring manual mapping totaxonomies and existing databases. AVAILABILITY:http://bioatlas.compbio.sdu.dk/.