Hindu cosmology counts time in units that go up to a Brahma's lifetime, and the numbers are given explicitly enough to be checked. They check out. What is more interesting than the size of the figures is what the scheme is for — and the principle it produces, called kalpa bheda, which is the tradition's own explanation for why its texts do not always agree.
⏳ The Units
Yuga: the four ages, in the ratio 4 : 3 : 2 : 1
Mahayuga: all four together — 4,320,000 human years
Manvantara: 71 mahayugas, plus a junction — presided over by a Manu
Kalpa: 14 manvantaras = one day of Brahma — 4.32 billion years
Brahma's life: 100 Brahma-years — a para
Now: Kali Yuga, 28th mahayuga, Vaivasvata manvantara, Shveta Varaha kalpa
📑 Table of Contents
4️⃣ The Four Yugas
| Yuga | Divine years | Human years | Ratio | Dharma stands on |
|---|---|---|---|---|
| Satya / Krita | 4,800 | 1,728,000 | 4 | Four legs |
| Treta | 3,600 | 1,296,000 | 3 | Three legs |
| Dvapara | 2,400 | 864,000 | 2 | Two legs |
| Kali | 1,200 | 432,000 | 1 | One leg |
| Total (mahayuga) | 12,000 | 4,320,000 | 10 | — |
💡 Where the multiplier comes from
A divine year is 360 human years, on the standard reckoning that a human year is a day and night of the gods. So 12,000 × 360 = 4,320,000. Every figure in the scheme derives from this one multiplication, which is why all of them end in the same digits.
🔭 The Larger Units
| Unit | Composition | Human years |
|---|---|---|
| Mahayuga | 4 yugas | 4,320,000 |
| Manvantara | 71 mahayugas + a sandhi junction | ≈ 306,720,000 + junction |
| Kalpa — a day of Brahma | 14 manvantaras + 15 junctions = 1,000 mahayugas | 4,320,000,000 |
| Brahma's day + night | 2 kalpas | 8,640,000,000 |
| Brahma's year | 360 such days and nights | ≈ 3.1 trillion |
| Brahma's life — a para | 100 Brahma-years | ≈ 311 trillion |
📌 The arithmetic, checked
14 manvantaras × 71 mahayugas = 994 mahayugas. The 15 sandhi junctions (one before the first manvantara, one after each) are each 4/10 of a mahayuga — the length of a Satya Yuga — giving 15 × 0.4 = 6. And 994 + 6 = 1,000 mahayugas exactly. The scheme is internally consistent, and the junctions exist precisely to make it come out round.
👤 The Fourteen Manus
Each manvantara is presided over by a Manu, with its own Indra, its own set of devas and its own seven sages — the Sapta Rishis of that period.
| # | Manu | |
|---|---|---|
| 1 | Svayambhuva | Past |
| 2 | Svarochisha | |
| 3 | Uttama | |
| 4 | Tamasa | |
| 5 | Raivata | |
| 6 | Chakshusha | |
| 7 | Vaivasvata | Current — son of Vivasvan, the sun; the Manu of the flood account |
| 8 | Savarni | Future |
| 9 | Daksha Savarni | |
| 10 | Brahma Savarni | |
| 11 | Dharma Savarni | |
| 12 | Rudra Savarni | |
| 13 | Deva Savarni | |
| 14 | Indra Savarni |
💡 Manu and the fish
The current Manu, Vaivasvata, is the one warned by the fish — Matsya — of the coming deluge, who preserves the seeds of life and the Vedas in a boat. The account appears in the Shatapatha Brahmana in an early form, and in the Matsya, Bhagavata and other Puranas with additions. That the Manu of the flood is the Manu of our manvantara places the story at the beginning of the present cycle rather than in an undated past.
📍 Where We Are Said To Be
| Level | Position |
|---|---|
| Brahma's life | The 51st year, on the standard reckoning |
| Kalpa | Shveta Varaha Kalpa — the white boar kalpa |
| Manvantara | The 7th — Vaivasvata |
| Mahayuga | The 28th of that manvantara |
| Yuga | Kali, the fourth |
| Start of Kali Yuga | Traditionally 3102 BCE, at the departure of Krishna |
🔄 Kalpa Bheda
📌 The principle, and why it matters for reading
The cycles repeat — but they do not repeat identically. Each kalpa has its own Manus, its own sages, its own sequence of events, and the same figures recur with differences. This is the doctrine of kalpa bheda, difference of cycle, and the tradition uses it as its own explanation for divergences between texts.
So when the Shiva Purana and the Vishnu Purana give different accounts of the same episode, or when the Ramayana's tellings differ in a detail, or when two Puranas list the Sapta Rishis differently — the tradition's position is not that one is wrong. It is that each text is faithfully recording the cycle it saw. The Puranas say so explicitly at several points, framing their narratives as belonging to a particular kalpa.
💡 What the scheme is for
Notice the effect of the numbers on the reader. Placed inside a scheme where a single day of Brahma is 4.32 billion years and we are in the 51st of his hundred years, a human life, a dynasty, an empire and a civilisation are all indistinguishably brief. The Puranas use the arithmetic rhetorically, and the passage that follows a time-calculation is very often about detachment. The numbers are an argument.
❓ Frequently Asked Questions
How long are the four yugas?
Satya 1,728,000, Treta 1,296,000, Dvapara 864,000, Kali 432,000 human years — a ratio of 4:3:2:1, totalling 4,320,000 per mahayuga. They derive from 12,000 divine years × 360 (a human year being a day and night of the gods), which is why every figure ends in the same digits.
What is a kalpa?
A day of Brahma — fourteen manvantaras with their junctions, equalling 1,000 mahayugas or 4.32 billion human years. The arithmetic checks: 14 × 71 = 994, plus 15 junctions of 0.4 mahayuga = 6, giving exactly 1,000. The junctions exist precisely to make it come out round.
Which manvantara are we in?
The seventh, Vaivasvata — presided over by the Manu who is the son of Vivasvan the sun, and who is warned by the fish of the deluge and preserves the seeds of life and the Vedas in a boat. Six are past and seven to come. Each manvantara has its own Indra, its own devas and its own seven sages.
When did the Kali Yuga begin?
Traditionally 3102 BCE, at the departure of Krishna — the reckoning used in the Indian calendrical tradition and fixed by the astronomical siddhantas, Aryabhata's in particular. It is a calculated date within that system, not an independently attested historical event. On it, the Kali Yuga is a little over 5,100 years old, with about 427,000 remaining.
What is kalpa bheda?
The principle that the cycles repeat but do not repeat identically — each kalpa has its own Manus, sages and sequence of events. The tradition uses it as its own explanation for divergences between texts: when two Puranas give different accounts, the position is not that one is wrong but that each text is faithfully recording the cycle it saw. The Puranas frame their narratives as belonging to a particular kalpa.
🙏 Conclusion
The scheme is arithmetically tidy — 994 mahayugas plus fifteen junctions of four-tenths each, coming out at exactly a thousand — and it places the present moment in the 28th mahayuga of the seventh manvantara of the 51st year of a Brahma. Its most useful product is not the size of the figures but kalpa bheda: the principle that the cycles repeat without repeating identically, which is how the tradition accounts for its own texts disagreeing without having to call any of them wrong.