The performance of the model for solid solubility in organic solvents when using the model predictions for the aqueous solubility as the reference solid solubility is given in Figure (left, blue). The solid solubility of the 1051 datapoints at 298K can be predicted with a RMSE/MAE of 0.89/0.62 log(mol/L). When the results for individual solutes in a range of organic solvents are studied in detail, trends are observed in the deviations from the experimental data. This can be seen in Figure for 1-chloroanthraquinone, phenothiazine, benzoin, and 4-nitrobenzoic acid. The experimental data for those solutes originate from the publications by Dai et al., Flanagan et al., Grubbs et al., Hoover et al., Saifullah et al., Stephens et al., Strickland et al., Yang et al., and Zhu et al. In the supporting information (Figure ), the same analysis is made for the 40 solutes that are most common in the database at 298K. As can be seen in Figure (blue), the solid solubility of some solutes is predicted very well, whilst a constant deviation from the parity line is observed for others. In the latter case, the absolute value of the predicted solid solubility is off, but the relative solid solubility between various organic solvents is well captured by the model. This is the case, for example, for benzoin and 4-nitrobenzoic acid in Figure (blue). The main reason for the constant deviation of log(S X,298K ) in different solvents from the parity line is the inaccurate prediction of the aqueous solid solubility of that solute. Predictions of log(S X,298K ) can be improved by using experimental data for the solid solubility of that solute in a different solvent as the reference solid solubility in Eq. 3. This is demonstrated by using all experimental data in the CombiSolu-Exp database that are measured in ethanol at 298K as a reference for the calculations of log(S X,298K ) in other solvents.