Question
Which scripture mentions Yuga length?
Answer
I have given below a discussion of the length of the yugas in Linga Purana.
O brahmins, the Krta yuga consists of four thousand years. Four hundred, three hundred, two hundred and hundred years respectively constitute the period of transition both at the beginning and end of a yuga. [1]
Linga Purana I.4.5-6
[1] Each Yuga is prefixed and suffixed by a sandhya which specifies the advent and culmination of yuga. The two sandhyas of a yuga are of equal length though their period of duration differs from yuga to yuga. Thus Krta Yuga lasts for four thousand divine years and its sandhyas for eight hundred such years; Treta lasts for three thousand divine years and its sandhyas for six hundred such years; Dvapara lasts for two thousand years and its sandhyas for four hundred; Kali lasts for one thousand and its sandhyas for two hundred such years. The total period for the four yugas is ten thousand divine years and that for their sandhyas is two thousand divine years.
The amsaka, therefore, is one-sixth of the duration of each yuga. The period of duration of Treta, Dvapara and kali is respectively three thousand, two thousand and one thousand years without their amsaka parts.
Linga Purana I.4.7-8
The above two passages give us the duration of the yugas in divine years. Now we have to change the duration into human years.
The people who know arithmetic say that the three hundred and sixty thousand human years constitute the period of a thousand divine years.
Linga Purana I.4.23
The duration of a yuga is calculated according to the divine reckoning. The first yuga is name Krta; thereafter comes Treta and then Dvapara and Kali. O men of holy rites, these are the (names of the four) yugas. Henceforth the number of years of each yuga which have been mentioned earlier in divine reckoning are now being counted according to human reckoning. The Krta consists of one million four hundred and forty thousand human years; Treta of one million eighty thousand years; Dvapara of seven hundred twenty thousand years and Kali of three hundred and sixty thousand human years; Thus the duration of the four yugas without the period of junction and transition totals to three million six hundred thousand human years. If Sandhya period is included, the set of four ages will consist of four million three hundred and twenty thousand years.
Linga Purana I.4.24-30
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