The database presents a collection of in vitro mutation induction data after photon and particle beam irradiation. The experiments included in the database were all performed by means of the hprt mutation assay. The collection was based on extensive literature search, and contains data published in the time period from 1977 to 2002. As better described in the README file, the database provides information on RBE for cell killing and mutation induction, as well as dose response curves raw data for both endpoints, as digitised (when available) from the original publication. This study is part of a manuscript that was submitted for publication in April 2022.