Open-Source Licenses and Third-Party Resources
Last updated: October 13, 2026
KnowYourBaZi relies on several pieces of open-source software for calendar conversion, astronomical calculation and member login, and the page fonts are open-source fonts too. Their authors chose to share their work openly; the Site uses each under its own license and lists the copyright notices here. The script files the Site serves with its pages also keep the original authors' license notices in their headers.
1. Code downloaded to your browser with the pages
| Name | Used for | License | Copyright |
|---|---|---|---|
| lunar-javascript | Gregorian–lunar conversion, solar terms and the stem-branch calendar (the basis of the BaZi Four Pillars and the almanac); served on the Site as the minified file /js/lunar.js | MIT | Copyright (c) 2020 6tail |
| Astronomy Engine | Planetary positions for birth charts, moon phases, eclipses and tonight's sky; served on the Site as /js/astronomy.min.js | MIT | Copyright (c) 2019-2023 Don Cross |
| html2pdf.js (including jsPDF and html2canvas) | The "Download PDF" feature of the in-depth reading; loaded from cdnjs only when you press the button | MIT | Copyright (c) 2017 Erik Koopmans and the authors of each package |
| d3-celestial star catalog (BSD-3-Clause) | Bright stars, the 88 Western constellation lines and the 28 lunar mansions for the tonight's-sky tool; on this site as /js/xingkong-data.js (a trimmed adaptation). Star positions come from the Hipparcos catalogue | BSD-3-Clause | Copyright (c) 2015, Olaf Frohn |
| Chinese asterism lines from Stellarium sky culture data (CC BY-SA 4.0) | The Chinese asterism lines in the tonight's-sky tool, stored in the C field of /js/xingkong-data.js; our adaptation is offered under CC BY-SA 4.0 as well | CC BY-SA 4.0 | Contributors to the Stellarium sky culture data |
| Unicode Unihan database (Unicode License v3) | Kangxi stroke counts for name numerology and the radical table for BaZi baby names; on this site as /js/xingming-data.js and /js/qiming-radical.js (derived data) | Unicode License v3 | Copyright © 1991-2024 Unicode, Inc. |
2. Code that runs on the server
| Name | Used for | License |
|---|---|---|
| Better Auth and its dependencies | Member sign-up, login and account management | MIT (dependencies under their own licenses) |
3. Fonts
The fonts used on the pages, Cormorant Garamond, Jost, Noto Serif TC, Noto Serif SC, Noto Serif JP and Noto Serif KR, are loaded through the Google Fonts service. All are licensed under the SIL Open Font License 1.1, and copyright belongs to each font's authors.
4. Open-source projects used for cross-checking during development
The following projects are not downloaded with the pages; they are used only during development to check the results of the Site's own engines:
- iztro (MIT): used to check Zi Wei Dou Shu chart casting, the four transformations and how the monthly and daily cycles are started. The Site's table of major-star brightness follows the system table in the Complete Book of Zi Wei Dou Shu (Ziwei Doushu Quanshu), the same one iztro uses.
- astronomy-engine, astronomia (MIT) and circular-natal-horoscope-js (Unlicense): used to check birth chart, solar term and astronomical calculations.
5. Classical texts and scriptures
The original texts of the classical books, fortune poems and Taoist scriptures transcribed on the Site are very old and in the public domain; some scriptures were collated against public editions such as Wikisource. The plain-language versions, translations and notes beyond the original texts are mainly generated by AI and then selected, edited and reviewed by the Site; what the Site claims is the selection, arrangement and editing of that content. For how it may be reused, see the Terms of Use.
6. Full text of the MIT License
The software marked MIT above is licensed under the following terms (see the tables above for each project's copyright holders):
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
7. Full text of the BSD 3-Clause License
The d3-celestial star catalog above is licensed under these terms; its copyright notice and conditions are:
Copyright (c) 2015, Olaf Frohn All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
8. Full text of the Unicode License v3
The Unicode Unihan derived data above is licensed under these terms; the copyright and permission notice is:
UNICODE LICENSE V3 COPYRIGHT AND PERMISSION NOTICE Copyright © 1991-2024 Unicode, Inc. NOTICE TO USER: Carefully read the following legal agreement. BY DOWNLOADING, INSTALLING, COPYING OR OTHERWISE USING DATA FILES, AND/OR SOFTWARE, YOU UNEQUIVOCALLY ACCEPT, AND AGREE TO BE BOUND BY, ALL OF THE TERMS AND CONDITIONS OF THIS AGREEMENT. IF YOU DO NOT AGREE, DO NOT DOWNLOAD, INSTALL, COPY, DISTRIBUTE OR USE THE DATA FILES OR SOFTWARE. Permission is hereby granted, free of charge, to any person obtaining a copy of data files and any associated documentation (the "Data Files") or software and any associated documentation (the "Software") to deal in the Data Files or Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, and/or sell copies of the Data Files or Software, and to permit persons to whom the Data Files or Software are furnished to do so, provided that either (a) this copyright and permission notice appear with all copies of the Data Files or Software, or (b) this copyright and permission notice appear in associated Documentation. THE DATA FILES AND SOFTWARE ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THE DATA FILES OR SOFTWARE. Except as contained in this notice, the name of a copyright holder shall not be used in advertising or otherwise to promote the sale, use or other dealings in these Data Files or Software without prior written authorization of the copyright holder.
9. Contact us
If you are an author of one of the projects listed above and find that our attribution is wrong or missing something, please let us know: [email protected].