pysweph 2.10.3.3

Community fork of Pyswisseph, a Python extension to the Swiss Ephemeris

pysweph

Modern Python bindings for the Swiss Ephemeris, a high-precision astronomical computation library for astrology developed and maintained since 1997.

pysweph continues the work of astrorigin/pyswisseph with updated documentation, bug fixes, and ongoing community maintenance.

Background

In mid-2025, the documentation for Pyswisseph (astrorigin.com/pyswisseph) became inaccessible, and the maintainer has been unresponsive to issues and pull requests. This fork, pysweph, aims to keep the Python interface stable, documented, and installable for users who rely on it.

Upstream and scope

pysweph links directly to the official Swiss Ephemeris C library maintained by Alois Treindl and Astrodienst.

The previous Python package (astrorigin/pyswisseph) included Stanislas Marquis’ auxiliary repositories (swephelp, sqlite3, and related utilities). These have been intentionally removed in pysweph to reduce complexity and depend only on the canonical Swiss Ephemeris source.

What's new in pysweph

• Full documentation rebuild using Sphinx and MyST Markdown, following the Diataxis framework
• Regenerated API reference directly from Python docstrings
• Original tutorials and conceptual guides.
• Bug fixes improving error handling in swe.calc() functions and swe.deltat_ex
• Continuous integration and Github Pages documentation hosting
• Compatible with the upstream Swiss Ephemeris C library

You can browse the documentation here: https://sailorfe.github.io/pysweph.

Installation

pyswisseph is available directly from PyPI.

uv pip install pysweph
# or
pip install pyswseph

pysweph is a drop-in replacement for pyswisseph. As long as you uninstall pyswisseph from any existing project first, your import should still be

import swisseph as swe

Versioning

This project follows the versioning scheme: <swe_major>.<swe_minor>.<swe_patch>.<wrapper_increment>

• The first three numbers match the Swiss Ephemeris C library version.
• The fourth number increments for Python wrapper changes.
• Current C library version: 2.10.3 (released 2022).

pysweph starts from pyswisseph==2.10.3.2. The first release of this fork is 2.10.3.3.

If the original maintainer of pyswisseph returns, this project will coordinate or merge changes as appropriate.

Credits

• Alois Treindl, creator of the Swiss Ephemeris
• Stanislas Marquis, author of the original Python bindings (pyswisseph)
• sailorfe, maintainer of pysweph continuation

License

pysweph is licensed under the GNU Affero General Public License version 3, whose text you can read at LICENSE.