Partition Coefficient (LogP) Calculator

Add molecular fragments and their counts to estimate LogP. See a color-coded interpretation and Lipinski Rule of Five check.

Add Fragments

No fragments added yet.

Count: 0 fragment type(s)

Quick presets

Estimated LogP

—
Add fragments to compute
−30358+
HydrophilicDrug-like zoneLipophilic
Lipinski Rule of Five — LogP criterion
Compute LogP first

Fragment contributions

No fragments yet.

Fragment LogP reference table

Fragment Type Contribution
CH3Methyl+0.89
CH2Methylene+0.66
CHMethine+0.35
CQuaternary C+0.16
Ar C-HAromatic C-H+0.13
Ar CAromatic C (subst.)−0.13
OHAlcohol−0.67
Ar-OHPhenol−0.44
OEther−0.55
C=OKetone/Aldehyde−0.55
COOHCarboxylic acid−0.11
COOEster−0.55
NH2Primary amine−1.03
NHSecondary amine−0.49
NTertiary amine−0.19
FFluorine+0.14
ClChlorine+0.60
BrBromine+0.60
IIodine+1.00
SThioether+0.48

Summary

Add molecular fragments and their counts to estimate LogP. See a color-coded interpretation and Lipinski Rule of Five check.

How it works

  1. Choose a molecular fragment from the dropdown and enter the count (how many times it appears in the molecule).
  2. Click "Add Fragment" to add it to your fragment list.
  3. Repeat for all functional groups and carbon skeleton fragments in your molecule.
  4. The estimated LogP updates automatically as you add or remove fragments.
  5. Read the color-coded interpretation and Lipinski Rule of Five result below the value.

Use cases

  • Estimate membrane permeability of a drug candidate during early-stage discovery.
  • Check whether a compound falls within the Lipinski drug-likeness criteria before synthesis.
  • Compare the lipophilicity of structural analogs when designing lead optimization.
  • Screen environmental contaminants for bioaccumulation potential using LogP estimates.

Frequently Asked Questions

Last updated: 2026-06-18 · Reviewed by Nham Vu