Proposed calendars

calendar era that uses 10,000 BC as 1 HE

proposed reform of the Gregorian calendar, consisting of 4 quarters, each consisting of 3 months of length 31, 30 and 30, with an extra day after December and (on leap years) after June

system of time-keeping for future human settlers on Mars

perennial calendar proposal with fixed weekdays

significant revision of a calendar system

13 month solar calendar

The Symmetry454 calendar (Sym454) is a proposal for calendar reform created in early 2004 by Dr. Irv Bromberg, an assistant professor at the University of Toronto, Canada (retired in 2018). It is a perennial solar calendar that conserves the traditional month pattern and 7-day week, has symmetrical equal quarters, and starts every month on Monday.

proposal for calendar reform

proposal calendar having 13 months per year and a leap week