We have 4 eras like a Satiyuga, Dwaparayuga, Tretayuga, Kaliyuga.
I have read all of the time periods. But, Is this calculation linked to any other criteria like increment of sins on earth or anything else?
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From Manu Smriti:
1.69. They declare that the Krita age (consists of) four thousand years (of the gods); the twilight preceding it consists of as many hundreds, and the twilight following it of the same number.
1.70. In the other three ages with their twilights preceding and following, the thousands and hundreds are diminished by one (in each).
1.71. These twelve thousand (years) which thus have been just mentioned as the total of four (human) ages, are called one age of the gods.
1.72. But know that the sum of one thousand ages of the gods (makes) one day of Brahman, and that his night has the same length.
So, no, the calculation is not based on the things you've mentioned but solely on some fixed time periods.
But, each Yuga is also typified by certain features like- increase of sins, lack of righteousness or the opposites etc.
1.81. In the Krita age Dharma is four-footed and entire, and (so is) Truth; nor does any gain accrue to men by unrighteousness.
1.82. In the other (three ages), by reason of (unjust) gains (agama), Dharma is deprived successively of one foot, and through (the prevalence of) theft, falsehood, and fraud the merit (gained by men) is diminished by one fourth (in each)
1.86. In the Krita age the chief (virtue) is declared to be (the performance of) austerities, in the Treta (divine) knowledge, in the Dvapara (the performance of) sacrifices, in the Kali liberality alone.
But, these features, are not contributing in deciding how long the Yugas will be. They are already fixed.