One of the longest measurements of time appears in ancient Hindu scriptures: the mahā-kalpa, equal to 311.04 trillion years.

Astronomical measurement and calculation have given us a pretty good idea of the age of the universe: approximately 13.7 billion years. That sounds like a lot, and it is a lot, but it’s tiny compared to the measures of time in Hindu cosmology.
Brahma (pictured above) is one of the three supreme divinities in many branches of Hinduism. Brahma is the creator, Vishnu is the preserver, and Shiva is the destroyer of the world. Through their efforts, the universe is made and unmade and made again in a perpetual cycle. And some Hindu texts put a deadline on that cycle of creation and destruction. A very long deadline.
To understand the scale here, we’re going to begin with the small cycles and work our way up. The Yuga Cycle represents the four ages of humanity. It begins with a golden age, the Satya Yuga, where truth and goodness reign supreme, disease is unknown, and all is well. After 1,728,000 years of this utopia, the world slips into the Treta Yuga. The world loses one quarter of its virtue and the sins of civilisation begin to rise… but it only lasts three quarters of the time (1,296,000 years). The Dvapara Yuga comes next. Now the world is half virtue and half sin, and it’s half the length of the golden age (864,000 years). Finally, we get to the Kali Yuga. It’s the worst, and it’s the shortest, and that’s the age we’re in now. Our current Kali Yuga began 5,122 years ago. But don’t worry, it’s scheduled to end in only another 426,878 years.
So, a full Yuga Cycle lasts 4,320,000 years, and they repeat over and over. But that’s just part of a larger cycle: the manvantara. Every seventy-one Yuga Cycles there’s an apocalyptic event (a Noachian flood). A new progenitor of humankind emerges, the Manu who guides humanity through the world’s destruction. We’re about halfway through our current manvantara. The whole thing lasts 306,720,000 years.

Next cycle! Fourteen manvantaras, with a watery gap of 1,728,000 years between each of them, together make a kalpa. The kalpa lasts 4.32 billion years, and is followed by a pralaya of equal length. Together they represent another circle of global (or universal) creation and destruction. And this is where we finally get to Brahma, the creator god. One kalpa represents one day for Brahma. One pralaya represents one night for Brahma.
You can probably guess where this is going. Thirty days and nights of Brahma equal a Brahma month, 259.2 billion years. Twelve months make a Brahma year, 3.11 trillion years. And Brahma’s full lifespan – the mahā-kalpa – is a hundred years for him, 311.04 trillion years for us.
According to Hindu accounts, Brahma is currently middle-aged. But when he finally ceases to exist another Brahma will emerge. The cycle of a human life, death, and rebirth is reflected and reflects greater and longer circles of creation and destruction – of civilisations, of epochs, of the world, and of the divine.