Calendars

by Hla Min

Updated : Aug 2025

• A solar calendar is based on the orbit of the earth around the sun.
  Typically, it takes 365.2422 solar days to complete the orbit.
  A leap year attempts to adjust the calendar by adding an extra day every four years.
• A lunar calendar is based on the orbit of the moon around the earth.
  Typically, it takes 29.6 days to complete a cycle.
• A luni-solar calendar is a “hybrid” calendar that uses “lunar” month and “solar” year.
  The calendars used by Chinese and Vietnamese have 12 months in a year and an extra month in the year in which the Lunar and Solar Calendars are synchronized.
  The CNY (Chinese New Year) and Tet (Vietnamese New Year) occur in late January or early February.
• Julian Calendar
  Leap year : if a year is divisible by 4
• Gregorian Calendar
  Leap year :
  if a Century year is divisible by 400
  Other years if divisible by 4
• Burmese Calendar
  The Burmese use a Luni-Solar-Socio-Religious Calendar.
  It is used for social and religious events.
  There are 12 lunar months with a total of 355 days in a Common Burmese Year.
  There is a difference of 10 days with a Common Year in the Gregorian Calendar.
  An inter-calary month named “Second Waso” is usually added every three years to sync again with the Solar Calendar.
  It is known as “Wah Htutt”.
  If needed, an additional day is added in “Wah Gyi Htutt”.
• Civil Calendar
• Academic Calendar
• Appointment Calendar