Introduction
ExoCTK is an open-source, modular data analysis package focused primarily on atmospheric characterization of exoplanets. The subpackages included are:
Contamination and Visibility Calculator
Integrations and Groups Calculator
Transit Light-Curve Fitter
Limb Darkening Calculator
Phase Constraint Calculator
Atmospheric Forward Modeling
For more information on each package visit our documentation at readthedocs.
Most packages are also available through interactive tools at our web portal.
Installation
The following are instructions on how to install the exoctk package for both users and contributors. The exoctk repository provides a conda environment containing all of the dependencies needed to install and execute the exoctk software.
Download Anaconda or Miniconda
You must first have a working installation of conda (or mamba) for Python 3. If you do not yet have this on your system, you can visit the following links for download and installation instructions:
Obtain the exoctk Package
To obtain the exoctk package with the necessary environment file, clone the repository directly from GitHub:
git clone https://github.com/ExoCTK/exoctk.git
cd exoctk
Environment Installation
You can create the ExoCTK conda environment via the exoctk-env.yml file with the following conda (or mamba) command:
conda env create -f exoctk-env.yml
One can activate the newly-created environment with:
conda activate exoctk-env
After activating the environment, install exoctk from the cloned source.
Package Installation From Source
To install the latest development version of exoctk use pip to install directly from the cloned source:
pip install -e .
Obtain the exoctk Data
To obtain the necessary data to run ExoCTK, you just need to execute the exoctk.utils.download_exoctk_data() function. This function will download a series of compressed files, extract the files, and organize them into an exoctk_data/ directory. Note that this can only be done once the exoctk package has been fully installed (see instructions above).
Lastly, export an environment variable for EXOCTK_DATA.
For Mac OS/Linux, add the line
export EXOCTK_DATA='/path/to/your/unzipped/directory/exoctk_data/'
to your .bashrc or .bash_profile.
For Windows, add an environment variable using System Utility.
Missing Dependencies?
If you find that the exoctk environment is missing a required dependency, please feel free to submit a GitHub Issue detailing the problem.
Citation
If you use ExoCTK for work/research presented in a publication (whether directly, or as a dependency to another package), we recommend and encourage the following acknowledgment:
This research made use of the open source Python package exoctk, the Exoplanet Characterization Toolkit (Bourque et al, 2021).
where (Bourque et al, 2021) is a citation of the Zenodo record, e.g.:
@software{matthew_bourque_2021_4556063,
author = {Matthew Bourque and
Néstor Espinoza and
Joseph Filippazzo and
Mees Fix and
Teagan King and
Catherine Martlin and
Jennifer Medina and
Natasha Batalha and
Michael Fox and
Jules Fowler and
Jonathan Fraine and
Matthew Hill and
Nikole Lewis and
Kevin Stevenson and
Jeff Valenti and
Hannah Wakeford},
title = {The Exoplanet Characterization Toolkit (ExoCTK)},
month = feb,
year = 2021,
publisher = {Zenodo},
version = {1.0.0},
doi = {10.5281/zenodo.4556063},
url = {https://doi.org/10.5281/zenodo.4556063}
}
Want to stay up-to-date with our releases and updates?
Subscribe to our newsletter by sending an email with a blank body and subject to exoctk-news-subscribe-request@maillist.stsci.edu from the email you want to enroll. You should then receive a confirmation email with instructions on how to confirm your subscription, please be sure to do so within 48 hours.
Release files for exoctk 2026.7
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| exoctk-2026.7.tar.gz | 21.6 MB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| exoctk-2026.7-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 42.6 MB
Release files / exoctk-2026.7.tar.gz
| Download URL | exoctk-2026.7.tar.gz |
|---|---|
| Size | 21.6 MB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
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Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
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twine/7.0.0 CPython/3.13.14
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Transparency logRelease files / exoctk-2026.7-py3-none-any.whl
| Download URL | exoctk-2026.7-py3-none-any.whl |
|---|---|
| Size | 21.0 MB |
| Tags | Python 3 |
|
SHA-256 checksum How to use checksums |
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BLAKE2b-256 checksum How to use checksums |
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|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/7.0.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Aug 11, 2026.
Transparency log