Understanding massive numbers through the lens of time

August 5, 2025

We hear the words million, billion, and trillion quite a bit. And we know that a million is a lot, a billion is a whole lot more, and trillion is even more than that.

But here's a good way to see how big the difference actually is.

How long is a million seconds? ​

First, let me ask you a question: How long do you think a million seconds is? In terms of days, weeks, years, decades, or whatever.

Turns out it's 11.5 days.

That's it. Less than two weeks.

How long is a billion seconds? ​

Now, how about a billion?

A billion seconds is 31.7 years.

Think about that. A million seconds ago was last week. A billion seconds ago was 1993.

How long is a trillion seconds? ​

Okay, last one. How long do you think a trillion seconds is?

A trillion seconds is 31,689 years.

That's right. A trillion seconds ago, humans were still in the Stone Age. Writing hadn't been invented. Agriculture hadn't been invented. We were hunter-gatherers using basic tools.

The takeaway ​

Nothing profound here to say other than when you hear about a billion years or a billion dollars or that we have a deficit in the trillions, just remember this post.