These functionals and basis sets were chosen to balance speed and accuracy; while more accurate methods exist to calculate isotropic shieldings and J -couplings, many of these methods are prohibitively expensive for application in high throughput workflows. We used a linear scaling approach to compensate for the systematic errors of DFT calculations. We show that the fitting procedure developed herein enables the accurate identification of products, despite the relatively low accuracy of the DFT calculations. The HMCMC analysis is robust against small (ca. 0.1 ppm) errors in isotropic chemical shifts, but it cannot accommodate large errors in the predicted chemical shifts. The accu-racy of the isotropic shifts obtained from DFT calculations was improved by correlating the calculated isotropic shieldings to the experimentally observed isotropic shifts, rather than referencing the calculated chemical shifts to the calculated chemical shift of a standard compound, such as trimethylsilane (TMS). Kwan and Liu have shown that such calibrations serve as simple rovibrational corrections to the predicted isotropic shifts of the ground state conformations of small molecules. To create a calibration line, 33 experimental NMR spectra of compounds in CDCl 3 solvent were obtained from the Spectral Database for Organic Compounds (SDBS) (all compounds are listed in the Supporting Information). The selected compounds were subjected to the procedure above to obtain isotropic shieldings for non-labile protons. The error in the calibration curve shown in Fig. is 0.1 ppm and fits a functional form of δ iso CDCl 3 = -0.9548σ iso gas + 30.435 (1) in which δ iso CDCl 3 is the isotropic chemical shift in a CDCl 3 solvent environment and σ iso gas is the DFT-calculated isotropic nuclear shielding. This relationship was used to convert the nuclear shieldings calculated by DFT to isotropic chemical shifts.