Integration of Python with Microsoft Excel

We have substantial experience and technology integrating the Python language and interpreter with the Microsoft Excel application. We can offer complete applications based on this technology or consulting services helping you develop the application and environment you need quickly and efficiently.

NOTE: For all new projects we recommend open source xlwings see below for examples. We also have an open-source fully functional demonstrator available at ExPy.

Bayesian robust linear regression


Integration of Python into Excel opens a new and efficient way of developing new applications and functionality for Excel with some distinct advantages:

  • Python code can be easily developed and tested outside the Excel platform, enabling better quality control and revision management

  • There is a large number of high-quality libraries available for Python

  • The same underlying Python code can be used from within Excel as well as for web-based or GUI applications

  • Python is a standardised, platform and vendor neutral, language with free licensing that suitable for commercial, in-house, or open-source development

Our Current Technology

We currently use xlwings and are able to advise on extensions as well as us.

Our Previous Technology

The information below is left for historical interest as ExPy was one of the relatively early open source projects in this field.

Our technology is based on the standard CPython implementation ( and the Excel “C”-language API (i.e., Excel ‘‘.xll’’ files). Some of the advantages of this approach are:

  • Full compatibility with Python libraries, including those with compiled code (e.g., ‘‘numpy’’, ‘‘scipy’’) and maximum cross-platform compatibility

  • Easy installation, just unpack and add the XLL file to Excel as an Add-In

  • Python functions can be used as functions in Excel formulae, and new functions can be defined during run time and be immediately available in Excel

  • Advanced build chain allowing efficient automated builds on the Linux platform

See our open-source demonstrator ExPy