We compiled experimental UV/Vis absorption data from several of the largest openlyavailable datasets: Deep4Chem, ChemFluor, Dye Aggregation (DyeAgg), ChemDataExtractor (CDEx), and the Dye-Sensitized Solar Cell Database (DSSCDB). 1 Among the datasets listed in Table , these were the largest and most easily machine-readable, and they included solvent information for each measurement. All of these data sources reported the dyes in the form of SMILES, 33 but only the Deep4Chem set reported the solvents in this form. For the other four sets, we converted the solvent names and abbreviations to SMILES through a manually-constructed dictionary mapping because automatic tools did not recognize the necessary variety of names and abbreviations for many solvents. We extracted all measurements that included a valid dye SMILES string, solvent SMILES string, and peak wavelength of maximum absorption. We determined the validity of the SMILES strings using RDKit and dropped measurements with invalid dye or solvent SMILES (105 measurements) and those containing "." to represent clusters of molecules (373 measurements).