When applying nTABS to the Platinum set, TABS generally showed very good agreement with heavy-atom RMSD while still allowing important structural changes like small-ring conformations to be distinguished. The related nTABS, which counts the number of possible TABS that can be formulated for a molecule, provides a direct estimation for the upper bound of the size of the conformational space. Comparing nTABS with the size of a large RMSD-pruned ensemble of the molecule (number of conformers = 500'000 and RMSD threshold 0.5 Å ), a good correlation was observed.