We are now in Kali Yuga. It is now 2018, next year it is 2019. Back in time you see the appearance of the Lord Caitanya (18 feb 1486 - 1533 ). Going back there is the year 1000, then 0, then 4000 years BCE. This Kali-yuga began in the year 3102 BCE
Ask yourself the question who the ancestors of the old Kings of India where before the many invasions, you will end up in the time-table of Srimad Bhagavatam. It contains the entire history of mankind (it includes the itihasa, Ramayana and Mahabharata).
Our universe is the smallest with a diameter of 4 trillion miles and is 311040000000000 (311 trillion 40 billion years) years old. This is the time measured in earth calculations when Maha-Visnu (Karanodakasay Visnu, an expansion of the expansion of the expansion of Sri Krishna), breaths in or out (only 1 time).
When Maha-Visnu breaths out, millions of universes come out of the pores of His gigantic transcendental body. When He breaths in, all universes go back into His body. This is a description of how great Lord Krishna (God, the Supreme Person, the Creator, is). Gods invisible powers are His Eternal effulgent rays (as Brahman, worshiped by the impersonalists), He sits with complete Knowledge (as the Super Soul besides the soul in the heart of every living entity in the material universe, worshiped by the yogis)
The effulgent rays are shining from His transcendental body (as Bhagavan, in complete happiness, worshiped by the bhaktas). He is unknown to all non-satvic humans and known to the satvic humans. He is the Supreme Personality of Godhead, Bhagavan Krishna.
There are cycles of creation and destruction. Each cycle lasts 311040000000000 years. In the current cycle, our universe exists 155521970000000 years (155 trillion 521 billion 970 million years). We still have 155518030000000 years (155 trillion 518 billion 30 million years) to go before the end of the universe and current cycle approaches. The age of the universe is directly related to the age of a person called Brahma. Hij is the first living entity in the material universe created by Sri Krishna through His expansion Garbhodakasayu Visnu. Brahma lives 100 years which is called 1 Maha Kalpa. His 1 day (12 hours) is called a Kalpa which lasts 4320000000 years (4 billion 320 million years). So 100 years is: (1 day of Brahma[4320000000]x2(day+night)x30(days in a month)x12(months in a year)x100(years) = 311040000000000 years. (311 trillion 40 billion years)
The current age of Brahma is 50 years and he is now in his 1st day of his 51st year. 1 day of Brahma (12 hours) is divided in 14 parts called Manvataras. There is a partial creation and devastaion in the beginning and ending of each Manvantara. Between each Manvantara there is a juncture (Sandhya) of 1728000 years. In each Manvantara there is a different Manu, the first Human of a Manvantara.
We are now in the Kali Yuga. This lasts 432000 years (1200 years of the demi-gods). Before this you had the Dvapara Yuga, 864000 years (2400 years of the demi-gods), before this you had the Treta Yuga, 1296000 years (3600 years of the demi-gods) and before that you had the Satya Yuga, 1728000 years (4800 years of the demigods). Together this is called a Divya Yuga or Catur Yuga which lasts 4320000 years (12000 years of the demi-gods). This is called 1 Yuga Cucle. 1 day and 1 night of the demi-gods is 1 year on earth. 1 demi-god year is 360 years on earth.
1 Manvantara (1 life span of Manu) lasts 71 years of these Catur Yugas, or Dvipa yuga or Maha yugas (71x4320000) = 306720000 years.
1 Manvantara Juncture (Sandhya - Interval between Manvantaras) = 1728000 years. After each Manvantara follows one Saṃdhi Kāla of the same duration as a Kṛta Yuga (1,728,000 = 4 Charaṇas).
It is said that during a Saṃdhi Kāla, the entire earth is submerged in water.
1 Daytime of Brahma (14 Manvantaras[14x306720000]+15 Junctures[15x1728000]) = 4294080000 + 25920000 = 4320000000 years. (1 kalpa, day or night duration)
There are two Kalpas in a day and night (Adhi Sandhi) of Brahma.
14 Manvantaras = 1 kalpa for Brahma's 12 hour day-time and 1 kalpa for Brahma's 12 hour night.
There are 2 kalpas in a 24 hour day-night of Brahma
So we have already passed through the previous 6 Manvantaras in Brahma's day:
(6 Manvantaras[6x306720000 =1840320000]+27 CaturYugas[27x4320000 =116640000]+7 Manvantaras Junctures[7x1728000 =12096000]+Time passed in current Catur Yuga[1728000 +1296000 +864000 +5120 (kali yuga now started 3102bce + 2018) =3893120]): 1972949120 years
Time remaining in current day of Brahma (1 Day of Brahma - Time passed in current day) = 4320000000 - 1972949120 = 2347050880 years.
Age of current Manu (Vaivasvata)/Time passed in current Manvantara (27 catur yugas[27x4320000 =116640000]+Time passed in current Catur Yuga[1728000 +1296000 +864000 +5120 (kali yuga now started 3102bce + 2018) =3893120] = 120533120 years
1 Maha Kalpa (1 life of Brahma, 100 years) = (1 day of Brahma[4320000000]x2 kalpas(day+night)x30(days in one month)x12(months in a year)x100(years) = 311040000000000 years (311 trillion 40 billion years)
1 year of Brahma = 311040000000000 / 100 = 3110400000000 years (3 trillion 110 billion 400 million years)
1 month of Brahma = 3110400000000 / 12 = 259200000000 years (259 billion 200 million years)
1 day and night of Brahma = 259200000000 / 30 = 8640000000 years (8 billion 640 million years)
1 day or night of Brahma = 8640000000 / 2 = 4320000000 years (4 billion 320 million years). A Kalpa (12 hour day or a 12 hour night) each consists of a period of 4 Billion 320 Million human years followed by 14 Manvataras and Saṃdhi Kalas.
Current age of Brahma and Universum = (1 day of Brahma[4320000000]x2(day+night)x30(days in a month)x12(months in a year)x50(years) =155521970000000 years (155 trillion 521 billion 970 million years)
Time that remains till the end of Brahma and Universum = 1 Maha Kalpa - Current age of Brahma = 311040000000000 - 155521970000000 =155518030000000 years (155 trillion 518 billion 30 million years)
We are now 120533120 years in the current Manvantara (Vaivasvata). We are now 5120 years in Kali Yuga of the 28st Catur Yuga of the 7th Manvantara in the 1st day of Brahma in his 51st year.
From Sastra:
Bhagavad Gita As It Is, Chapter 8, Verse 17:
TEXT 17
sahasra-yuga-paryantam
ahar yad brahmaṇo viduḥ
rātriṁ yuga-sahasrāntāṁ
te 'ho-rātra-vido janāḥ
SYNONYMS
sahasra—thousand; yuga—millenniums; prayantam—including; ahaḥ—day; yat—that; brahmaṇaḥ—of Brahmā; viduḥ—know it; rātrim—night; yuga—millenniums; sahasra-antām—similarly, at the end of one thousand; te—that; ahaḥ-rātra—day and night; vidaḥ—understand; janāḥ—people.
TRANSLATION
By human calculation, a thousand ages taken together is the duration of Brahmā's one day. And such also is the duration of his night.
PURPORT
The duration of the material universe is limited. It is manifested in cycles of kalpas. A kalpa is a day of Brahmā, and one day of Brahmā consists of a thousand cycles of four yugas or ages: Satya, Tretā, Dvāpara, and Kali. The cycle of Satya is characterized by virtue, wisdom and religion, there being practically no ignorance and vice, and the yuga lasts 1,728,000 years. In the Tretā-yugavice is introduced, and this yuga lasts 1,296,000 years. In the Dvāpara-yuga there is an even greater decline in virtue and religion, vice increasing, and this yuga lasts 864,000 years. And finally in Kali-yuga (the yuga we have now been experiencing over the past 5,000 years) there is an abundance of strife, ignorance, irreligion and vice, true virtue being practically nonexistent, and this yuga lasts 432,000 years. In Kali-yuga vice increases to such a point that at the termination of the yuga the Supreme Lord Himself appears as the Kalki avatara, vanquishes the demons, saves His devotees, and commences another Satya-yuga. Then the process is set rolling again. These four yugas, rotating a thousand times, comprise one day of Brahmā, the creator god, and the same number comprise one night. Brahmā lives one hundred of such "years" and then dies. These "hundred years" by earth calculations total to 311 trillion and 40 billion earth years. By these calculations the life of Brahmā seems fantastic and interminable, but from the viewpoint of eternity it is as brief as a lightning flash. In the causal ocean there are innumerable Brahmās rising and disappearing like bubbles in the Atlantic. Brahmā and his creation are all part of the material universe, and therefore they are in constant flux.
In the material universe not even Brahmā is free from the process of birth, old age, disease and death. Brahmā, however, is directly engaged in the service of the Supreme Lord in the management of this universe-therefore he at once attains liberation. Elevated sannyāsīs are promoted to Brahmā's particular planet, Brahmaloka, which is the highest planet in the material universe and which survives all the heavenly planets in the upper strata of the planetary system, but in due course Brahmā and all inhabitants of Brahmaloka are subject to death, according to the law of material nature.
There are 1,000 cycles of Mahā-Yuga in one 12 hour day-time of Brahma and no Maha-yugas during Brahma's 12 hour night-time.
But still there is one Kalpa for his 12 hour day and one kalpa for his 12 hour night
So there are 2 Kalpas in Brahma's 24 hour day-night period known as a full day
One cycle of four Yugas is one Mahā-Yuga (4 million 320 thousand human years) . Thus a 12 hour day-time of Brahma is one Kalpa with a duration of 4 Billion 320 Million human years.
A day of Brahma equals 14 times 71 Mahā-Yuga, Catur yuga or Dvipa yuga) + (15 × 4 Charaṇas) = 994 Mahā-Yuga, Catur yuga or Dvipa yuga + (15 * 4,800) = 994 Mahā-Yuga,Catur yuga or Dvipa yuga + (72,000 years) [deva years] 6 = 12,000 [deva years] viz. one Maha yuga, Catur yuga or Dvipa yuga.
This equals 994 Mahā-Yuga, Catur yuga or Dvipa yuga then add another 6 Mahā-Yuga, Catur yuga or Dvipa yuga that gives the 1,000 Mahā-Yugas, Catur yuga or Dvipa yuga that exist during Brahma's 12 hour day-time.
Remember there are no Maha-yugas, Catur yuga or Dvipa yuga during Brahma's 12 hour night while Brahma is inactive due to sleeping. It is also during this 12 hour night-time of Brahma lasting 4 Billion 320 Million human years a partial annihilation of this universe takes place.
Currently, 50 years (155 Trillion 520 Billion human years) of Brahma have elapsed.
The last Kalpa at the end of 50th year is called Padma Kalpa.
We are currently in the first 'day' of the 51st year. (January 1st in human calculations)
Brahma's first 'day-time' of the 51st year Kalpa, is named as Shveta-Varaha Kalpa.
Within this day, six Manvantaras have already elapsed and this is the seventh Manvantara, named as Vaivasvatha Manvantara (or Sraddhadeva Manvantara).
Within the Vaivasvatha Manvantara, 27 Maha-yugas (remember, 4 Yugas together is a Mahayuga), and the Krita or Satya, Treta and Dwapara Yugas of the 28th Maha-yuga have elapsed.
This Kali-yuga is in the 28th Mahayuga.
This Kali-yuga began in the year 3102 BCE in the proleptic Julian Calendar.
Since 50 years or 155 Trillion 520 Billion human years of Brahma have already elapsed, this is the second Parardha, also called as Dvithiya Parardha.
We are in the 460th Maha-yuga during Brahma's day-time making it about 11.40 am during Brahma's first day-time in his 51st year.
Remember, there are 1000 Maha-yugas in Brahma's 12 hour day-time while non exist during his 12 hour night-time while he sleeps
A Catur yuga, Dvipa yuga and Maha yuga - ''A cycle of 4 Yugas''.
The Catur-yuga is also known as Divya-yuga or Maha-yuga and is made up of the four yugas -
''Satya-yuga, Treta-yuga, Dvapara-yuga, Kali-yuga''.
There are 1000 Catur-yuga, Divya-yuga or Maha-yugas in the 12 hour day-time of Lord Brahma (that takes 4 billion 320 million human years)
While there are no Catur-yugas, Divya-yuga or Maha-yugas in Brahma's 12 hour night-time (that also takes 4 billion 320 million human years) while Brahma sleeps as a partial annihilation takes place.
However, it is said both Lord Krishna in His original form and Lord Caitanya only come ''once'' in a day of Brahma, that ''day'' really means a ''day and night 24 hour period of Brahma'' that together over 24 hours takes 8 billion 640 million human years.
Presently ''our Kali-yuga'' where Lord Caitanya also came is happening in the very early morning of Brahma's ''day-time'' 11.40 am January 1st in Brahma's 51st
We are presently nearly half way into Brahma's 12 hour day-time which is the late morning being in the 460th Maha-yuga, Divya-yuga or Chatur-yuga out of a 1000.
Brahma's full day-time period of 12 hours takes 4 billion 320 million human years to happen.
Then night-time comes which is also 4 billion 320 million human years long.
A full 24 hour day is 8 Billion 640 Million human years
At night while Brahma sleeps and creates no Chatur-yuga, Divya-yuga Maha-yugas, our Universe is partially annihilated.
When the next day-time arrives at sunrise the cycle repeats itself for every day and night of Brahma's life
We are in the 28th Chatur-yugas, Divya-yuga or Maha-yuga in the ''Vaivasvata Manu'' (current) that has 71 Maha-yugas in it.
71 Chatur-yugas = 1 Manvantara (1 life span of Manu)
14 Manvantaras = 1 kalpa (1 day-time of Brahma)
We are in the 460th or 454th Maha-yuga also known as a Chatur-yuga or Divya-yuga
1 Svayambhuva Manu
2 Svarocisha Manu Vibhu
3 Uttama Manu Satyasena
4 Tapasa Manu Hari
5 Raivata Manu Vaikuntha
6 Cakshusha Manu Ajita
7 Vaivasvata Manu (current) Vamana
8 Savarni Manu Sarvabhauma
9 Daksha-savarni Manu Rishabha
10 Brahma-savarni Manu Vishvaksena
11 Dharma-savarni Manu Dharmasetu
12 Rudra-savarni Manu Sudama
13 Deva-savarni Manu Yogesvara
14 Indra-savarni Manu Brihadbhanu
There are 2 Kalpas in Brahma's full day of 24 hours not 1 as some believe
1 kalpa for his 12 hour day
1 kalpa for his 12 hour night
2 kalpas for a 24 hour day-night full day
Just a reminder, A Catur yuga, Dvipa yuga and Maha yuga - is made up of a cycle of 4 Yugas, Satya-yuga, Treta-yuga, Dvapara-yuga, Kali-yuga.
There are 1000 Catur-yuga, Divya-yuga or Maha-yugas in the 12 hour day-time of Lord Brahma (that takes 4 billion 320 million human years)
NOTE - there are no Maha-yugas, Catur-yuga or Divya-yuga in Brahma's 12 hour night-time (that also takes 4 billion 320 million human years) while Brahma sleeps as a partial annihilation takes place.
At night while Brahma sleeps no Chatur-yuga, Divya-yuga or Maha-yugas are created. This is because Brahma is sleeping and as he sleeps a partially annihilation of this Universe goes on for 4 billion 320 million (12 hours in Brahma's night-time period)
When the next day-time arrives at sunrise the cycle repeats itself for every ''day and night'' of Brahma's life
Lord Krishna in His original form and Lord Caitanya only come ''once'' in a day of Brahma, that ''day'' really means a ''day and night 24 hour period of Brahma'' that together over 24 hours takes 8 billion 640 million human years.
Lord Krishna in His original form and Lord Caitanya only come ''once' every 8 billion 640 million human years.
Taken from here