Partition coefficient calculator

Calculate the partition coefficient (K) which is the ratio of concentrations of a compound in two immiscible phases, typically octanol and water.

Input Parameters

Calculation Results

Partition Coefficient (K)

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Where:
K = Concentration in Octanol / Concentration in Water × Phase Volume Ratio
K represents how a compound partitions between octanol and water phases.

Interpretation:

  • K > 1: Compound prefers octanol
  • K < 1: Compound prefers water
  • K ≈ 1: Compound is equally soluble in both phases

Partition coefficient calculator Calculator Usage Guide

Learn how to use the Partition coefficient calculator and its working principles

What is a Partition Coefficient?

The partition coefficient (K) is a ratio that describes how a chemical substance distributes itself between two immiscible phases, typically octanol and water. It's an important parameter in pharmacokinetics, environmental science, and chemistry.

How to use this calculator

  1. Enter the concentration of the substance in octanol (mg/L)
  2. Enter the concentration of the substance in water (mg/L)
  3. Enter the phase volume ratio (typically 1 for standard octanol-water experiments)
  4. Click the "Calculate" button to compute the partition coefficient

Understanding the Results

The calculated partition coefficient (K) indicates the relative affinity of the compound for each phase:

  • A K value greater than 1 suggests the compound prefers the octanol phase (hydrophobic)
  • A K value less than 1 suggests the compound prefers the water phase (hydrophilic)
  • A K value close to 1 indicates the compound is equally soluble in both phases

Applications

Partition coefficients are used to:

  • Predict bioavailability of drugs
  • Assess environmental persistence and bioaccumulation potential
  • Optimize extraction processes in chemistry
  • Determine lipophilicity in drug discovery

Formula

Partition coefficient (K) = [Concentration in Octanol] / [Concentration in Water] × [Phase Volume Ratio]