The no-cost version of chemfp is available from ` PyPI`_ so if you use the third-party tools ` pip`_ or ` easy_install`_ then you can install it with one of:

pip install chemfp

easy_install chemfp

The chemfp tools depends on a working Python installation. You can download Python 2.7 from Note that older versions of OEChem only support up to Python 2.6. At some point chemfp will support Python 3.3 or later.

The core chemfp functionality does not depend on a third-party library but you will need a chemistry toolkit in order to generate new fingerprints from structure files. chemfp supports the free Open Babel and RDKit toolkits and the proprietary OEChem toolkit. Make sure you install the Python libraries for the toolkit(s) you select.

If you have a source version of chemfp then you will need a C compiler in order to compile it. This uses Python’s standard “”. Read for details of how to use it. The short version is that on Unix systems using sudo (that is, Mac OS X and most Linux-based OSes) you can do:

sudo python install

while for Windows you can do:

python install

Bear in mind Python 2.7 for Windows was built with Visual C++ 2008. The step does not work with Visual C++ 2010 or later unless you patch your local version of Python. The bug report is at .