Using the DF-MP2/aug-cc-pVQZ level of theory as reference method, the full set of 1283 cluster geometries were optimized and compared to several approximate methods using the algorithm described in Section 2.4. These methods have been chosen based on previous benchmarks on atmospheric molecular clusters and their wide application in cluster formation studies. Table presents the number of clusters labeled as "SameAsReference" and what fraction of the clusters this corresponds to for all the tested methods. It is seen that r 2 SCAN-3c, ωB97X-3c, ωB97X-D3BJ/6-31++G(d,p), and ωB97X-D3BJ/augcc-pVTZ finds the same minimum as the reference for more than 92% of the clusters indicating that these works very well for these types of systems. B97-3c also performs very well with 87% of the clusters as the same minimum geometry. This implies that the significantly cheaper r 2 SCAN-3c and ωB97X-3c methods might be a good alternative to the usually employed ωB97X-D3BJ/6-31++G(d,p) level of theory for obtaining the cluster strutcures.