Somewhere Between 6 Million and 90 Billion Books

In first grade, Dova has become quite the questioner when it comes to estimating quantities.  She recently came up with a question that I simply couldn't answer off the top of my head.  The conversation went something like this:

Dova:  Mom, how many books are there in the world?
Mom:  You mean the total number physical books or different books ever published?
Dova:  Different books.
Mom:  I have no idea.
Dova:  6 million?
Mom:  No, more than 6 million.
Dova:  90 billion?
Mom:  No, less than 90 billion.
Dova:  Then what??

I have no idea how parents used to answer these questions before the age of Google. My guess is simply with smiles and rolling eyes. Luckily, Google Books came to our rescue with this post, Inside Google Books: Books of the world, stand up and be counted! All 129,864,880 of you.

So I was actually right, there are somewhere between 6 million and 90 billion books ever written. In terms of order of magnitude, 130 million is actually right between 6 million and 90 billion.  Now Dova can say with authority that there were around 130 million books ever written.  Time to get cracking on reading them!