Harald Hammarström (born 1977 in Västerås, Sweden) is a Swedish linguist. He is currently an Associate Senior Lecturer at Uppsala University. Hammarström is especially known for his extensive work on curating Glottolog, a bibliographic database of the world's languages.
Hammarström has previously been employed as a researcher at the Max Planck Institute for the Science of Human History in Jena, Germany and at the Max Planck Institute for Psycholinguistics, in Nijmegen, Netherlands.
Glottolog is an open-access online bibliographic database of the world's languages. In addition to listing linguistic materials (grammars, articles, dictionaries) describing individual languages, the database also contains the most up-to-date language affiliations based on the work of expert linguists.
Glottolog was first developed and maintained at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and between 2015 and 2020 at the Max Planck Institute of Geoanthropology in Jena, Germany. Its main curators include Harald Hammarström and Martin Haspelmath.