Download of Chac 2.11.10 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The program is included in Productivity Tools. The bundle identifier for this application is com.Chac. This Mac app is a product of Warren Anderson. The most popular versions among the program users are 2.4, 2.3 and 2.1. We recommend checking the downloaded files with any free antivirus.
From the developer:
Chac is a complete, accurate Maya calendar application. It can find Maya calendar dates based on today's date, any date, a Long Count, Tzolk'in, Haab', Calendar Round, Julian day number, distance number, long reckoning, seatings in the cycle of God K, and convert between the Julian and Gregorian calendars. Chac can find the next heliacal or cosmical rising or setting of Venus and the visibility of the current inscription or date.
You may want to check out more Mac applications, such as DaliClock, MenuCalendarClock Entourage or Chronos, which might be related to Chac.