Install open-babel with Homebrew

Project links

• Homepage
• Upstream docs
• Package manager page

Commands and aliases

• obabel
• obconformer
• obdistgen
• obenergy
• obfit
• obfitall
• obgen
• obgrep
• obminimize
• obmm
• obprobe
• obprop
• obrms
• obrotamer
• obrotate
• obspectrophore
• obsym
• obtautomer
• obthermo
• roundtrip

Project history

Open Babel grew out of the older Babel molecular-format converter tradition into a collaborative open-source chemistry toolkit. The project describes itself as designed to speak the many languages of chemical data and to serve molecular modeling, chemistry, solid-state materials, biochemistry, and related areas.

The 2011 Journal of Cheminformatics paper presented Open Babel as an open chemical toolbox and reported that Open Babel 2.3 interconverted more than 110 formats. The paper framed the project as a response to the proliferation of chemical file formats and highlighted the need for algorithms beyond plain conversion, including aromaticity perception, partial charges, bond-order perception, and canonicalization.

The project continued through the 2.x line into 3.x with a plugin-oriented toolkit, command-line tools, language bindings, descriptors, fingerprints, force fields, coordinate generation, and release notes maintained as project documentation.

Adoption history

Open Babel is widely embedded in cheminformatics workflows because it is both a CLI and a library. Its GitHub README advertises ready-to-use programs, a programmer toolkit, format conversion, SMARTS searching, 2D and 3D coordinate generation, and support across molecular modeling, bioinformatics, organic chemistry, inorganic chemistry, solid-state materials, and nuclear chemistry.

Its adoption is visible in package managers, tutorials, wrappers, and scientific citations rather than in a single application platform. The supported-format documentation lists 146 formats in total, with 108 readable and 107 writable formats, which explains why downstream tools often shell out to obabel or link against Open Babel rather than maintaining their own converters.

How it is used

The typical user runs obabel to convert between formats, filter molecule files, search by SMARTS patterns, generate coordinates, add or transform properties, and prepare files for other chemistry tools. The package also ships many specialized executables for conformer generation, energy calculation, minimization, property reporting, RMSD, rotamers, symmetry, and thermochemistry.

Library users treat Open Babel as a chemistry interchange layer. Instead of writing a parser for every molecular format, applications can use Open Babel's C++ toolkit and bindings to import, transform, and export molecular structures while reusing its chemical perception and descriptor machinery.

Why package nerds care

Open Babel is a classic package-manager workhorse: not glamorous, but it collapses an ugly interoperability problem into one installed toolkit. Its value is amplified by the number of formats it hides from downstream packages and the breadth of small command-line programs it exposes.

For packagers, Open Babel is also a reminder that scientific CLI tools are often libraries with many executable front doors. ABI compatibility, plugin data, optional language bindings, and format support matter because other scientific packages may depend on Open Babel behavior without surfacing it directly to users.

Timeline

• Pre-Open Babel: Babel established the molecular-format conversion niche.
• 2011: the Open Babel chemical toolbox paper described version 2.3 and more than 110 interconverted formats.
• 2.x series: Open Babel accumulated conversion, searching, descriptor, coordinate-generation, and toolkit features.
• 3.x series: the documentation tracks Open Babel 3 releases and a modernized docs/API surface.

Related projects

• Open Babel overlaps with RDKit, CDK, Avogadro, cheminformatics file formats such as SMILES, InChI, SDF, MOL2, PDB, and CML, and toolchains for molecular modeling and computational chemistry. Its specific niche is broad format interoperability plus a command-line-first toolbox.

Sources

• https://github.com/openbabel/openbabel
• https://openbabel.org/docs/FileFormats/Overview.html
• https://openbabel.org/docs/Introduction/intro.html
• https://pubmed.ncbi.nlm.nih.gov/21982300/
• https://raw.githubusercontent.com/openbabel/openbabel/master/README.md
• source_facts.executables
• source_facts.package-manager