INTRODUCTION

How does Amazon sales rank work? Specifically, what factors affect the sales rank of books (or other products) at Amazon.com?

These questions will be answered in this article—as the result of years of research on this topic.

It’s easy to perform controlled experiments on Amazon.com sales rank. Here is the kind of research that went into the preparation of this article:

• I’ve purchased hundreds of books, e-books, and other products over the course of several years on Amazon, both directly from Amazon and through third-party sellers on Amazon. It’s easy to monitor the sales rank before and after each purchase.
• I’ve studied years of sales rank data for dozens of books that I’ve published. I’ve compared this data to royalty reporting and Nielsen Bookscan data from Author Central.
• Since 2008, there have been cases where I was able to make firsthand observations of purchases on Amazon, in which case…