logP vs logS vs logD: The Three Numbers Explained

By BioDockify Computational Research Team · September 4, 2026 · Concepts

logP, logS and logD demystified: what each number measures, when to quote which, the ionization trap between logP and logD, and thresholds that matter in drug design.

Read the complete article with tables, code and references on BioDockify.

Key References

• Mannhold R, Poda GI, Ostermann C, Tetko IV. Calculation of molecular lipophilicity: state of the art and comparison of logP methods on more than 96,000 compounds. J Pharm Sci. 2009;98(3):861-893. doi:10.1002/jps.21494
• Lipinski CA, Lombardo F, Dominy BW, Feeney PJ. Experimental and computational approaches to estimate solubility and permeability in drug discovery and development settings. Adv Drug Deliv Rev. 1997;23(1-3):3-25. doi:10.1016/0169-409X(96)00423-1
• RDKit documentation: Crippen logP contributions and logS models in the Descriptors module, rdkit.org.

Scope & Limitations

All three descriptors are equilibrium estimates on idealized states; formulation, salt form, and assay conditions shift the measured values the predictions approximate