2 pakshas in a month, shukla (waxing) and krishna (waning)
15 tithis in a paksha (1-14, 15th is purnima or amavasya)
60 ghatikas (or 30 muhurtas or 8 praharas) in a 24-hour period (ahoratra).
30 Kala (approx) in 1 muhurta
30 Kastha in 1 kala
15 Nimisha in 1 kastha
Years are synchronized with the solar sidereal year by adding a month every three years. The extra month is termed as "Adhik Mass" (extra month). This extra month is called Mala Masa (impure month) in Eastern India.
The Kali Era is not called a "Samvat" in common Indian usage, but since it Is also an era, it might be useful to mention it here too. The Hindu calendar article has more information on the Kali Era. The conversion is given here:
Add 3101 or 3100 (using the same guidelines as above) to the Gregorian year to get the number of elapsed Kali years.
Add 3102 or 3101 to get the current Kali yuga number.
Remember that the former (of the above two) is the standard, as explained at the Hindu calendar article.
This era also corresponds with Yudhisthira Samvat in which we have present year as 5115 (April 2013 AD)
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