Hindu units of time are described in Hindu texts ranging from microseconds to trillions of years, that also include cycles of cosmic time that repeat general events in Hindu cosmology. Time (kla) is described as eternal. Various fragments of time are described in the Vedas, the Manusmriti, the Bhagavata Purana, the Vishnu Purana, the Mahabharata, Surya Siddhanta etc.

Units of Time in the Vedas

Small Units of Time in the Vedas

• truti ()base unit = 0.30 s
• renu () 60 truti = 18 s
• lava () 60 renu = 1080 s
• lkaka () / 60 lava = 64.8 ms
• lipta () / 64.8 lkaka = 0.4 s
• vipala () / pala () / 60 lipta = 24 s
• vighai () / vind () / ghai () / 60 vighai 1.44 ks = 24 min
• nd () / danda () / muhrta () / 2 ghai 2.88 ks = 48 min
• nakhatra ahortram (sidereal day;  ) / 60 gha 86.4 ks = 24 hrs

Large Units of Time in the Vedas

• Kaliyuga = 4,32,000 human years
• Dwaparayuga = 8,64,000 human years
• Tretayuga = 12,96,000 human years
• Kritayuga = 17,28,000 human years
• 1 Chaturyuga = 43,20,000 human years
• 1000 Chaturyuga = 4,320,000,000 human years = 1 daytime of Brahma = one Mahayuga
• 1000 Chaturyuga = 4,320,000,000 human years = 1 night - time of Brahma
• 1 Brahma full day = 8,640,000,000 human years
• 1 Brahma month = 30 x 8,640,000,000 = 259,200,000,000 human years
• 1 Brahma year = 12 x 259,200,000,000 = 3,110,400,000,000 human years
• Brahma's age = 100 Brahma years = 311,040,000,000,000 human years
• 1 Brahma day = 14 manvantara = 1000 Chaturyuga = 4,320,00,00,000 human years

Manvantara

A cosmic day includes 14 Period or Manvantaras to 306 720 000 solar years. The next day, a cosmic unity is a Manvantara, there are fourteen pieces. A Manu mastered such a period. We live in the 7th Manvantara. Manvantara the first 6 have gone, 7 more will come. In particular, their names are:

1. Svaayambhuva - son of the self-born (here began the creation)
2. Svaarochisha - son of the Self Shining
3. Uttama - Son of the Most High
4. Taamasa - Son of Darkness
5. Raivata - son of wealth
6. Chaakshusha - son of the vision (this was the Quirlung instead of the milk ocean)
7. Vaivasvata - Vaivasvata is the son of the Sun God. We currently live here.
8. Arka Saavarni (or Savarnika) stands with the Sun God in relationship
9. Daksha-Saavarni - son of the rituals
10. Brahma-Saavarni - son of Brahma
11. Dharma-Saavarni - Son of the Eternal Law
12. Rudra-Saavarni - son of the Destroyer
13. Deva-Saavarni - Son of the Shining
14. Indra-Saavarni - son of the mighty Indra

How old is the universe on this day of Brahma?

The current Kali Yuga began after the Surya Siddhanta at midnight on a change of 17 at 18 February in the year 3102 BC in the proleptic Julian calendar. Since the beginning of the Kalpa until the year 2005 AD passed:

• 6 complete Manvantaras : 6 x 710
• 7-Manvantara twilight before a Manvantara each: 7 x 4
• 27 complete Mahayugas of the current 7th Manvantara: 27 x 10
• 3 Elapsed Yugas the current 28th Mahayuga: (4 + 3 + 2) x l
• 5107 solar years in the current Kali Yuga