Böttcher Score
Calculator

A web service that calculates molecular complexity as defined by Thomas Böttcher.

Features

What Böttch Score Calculator does

Molecular complexity score

Computes the Böttcher complexity score for any molecule directly from a SMILES string, delivering a single, interpretable number that reflects the overall structural complexity of the input molecule.

Per-atom breakdown

Provides a detailed atom-by-atom table of all contributing terms: connectivity diversity, elemental environment, chirality, valence, and bond order, so you can see exactly where complexity is concentrated in your molecule.

Visual output and data export

Generates a 2D structure diagram alongside the results and offers a one-click CSV download, making it straightforward to inspect results visually or integrate them into your own analysis workflows.

How to use

Launch the tool
Runs directly in your browser, no installation needed.

Input your molecule
Enter a SMILES string of your molecule.

Calculate
Submit and get the Böttcher score with a breakdown of contributing factors.

Cite the work
If you use results in a publication, cite the two papers listed below.

How to cite

If you use Böttch Score Calculator in your research, please cite both papers.

Paper 01

Synthetic, Mechanistic, and Biological Interrogation of Ginkgo biloba Chemical Space En Route to (−)-Bilobalide

Demoret, R. et al.

Journal of the American Chemical Society, 2020

doi.org/10.1021/jacs.0c08231

Paper 02

An Additive Definition of Molecular Complexity

Böttcher, T.

Journal of Chemical Information and Modeling, 2016

doi.org/10.1021/acs.jcim.5b00723

Service set up with the invaluable help of Ludovic Autin.

Ready to calculate?

Free, browser-based, no registration required.