tzolkin-calendar is a program and Python package (to use in your own code) that converts Gregorian dates to Maya Tzolk’in dates and vice versa. If you want to know more about the Maya calendar systems, see Some General Links.
Information about installing and the different ways to use tzolkin-calendar you find under Installation and Usage.
If you want to convert and calculate with Tzolk’in dates in your own code, see Usage of tzolkin-calendar in Your Python Code.
Contributing has information about how to contribute to tzolkin-calendar, by filing bug reports or feature requests, to contributing source code, to adding documentation or translations or any other way you can help tzolkin-calendar.
There are 3 interactive Jupyter Notebooks online at Binder, were you can get a fast overview of the possibilities of tzolkin-calendar. To start the interactive program, click to Kernel -> Restart & Run All.