Used with permission from an Amazon dealer.
Amazon Sales Rankings – Approximate, with observations about selling on Amazon.
The rankings that Amazon displays for
most of the books on the site are not an indication of how many copies have
These numbers are best used for Used and
Collectible copies. New books have different rules, very often the lowest
They are only a measure of the time since the most recent copy sold. That’s it.
For example (these numbers are from a dealer’s sales records):
Time since last sale Ranking (approx)
Just because a
book has a high ranking number, does not mean a copy won't sell tomorrow, just
as a low ranking
Ranking numbers tell you nothing about sales (if any)
previous to the most recent one. There could have been none
If a book has no
ranking number, that means Amazon has no record of it ever selling on their
site. That could be
Books that have
rankings that stay below 140k day after day, are continuously selling one or
more copies per day.
One other observation: Dealers with
higher feedback can sell their books for higher prices, and having a full
A different, updated view of Sales Rankings:
5,460,000 - 7,000,000 over 3 years ago
How does Amazon sales rank work?
Amazon sales rank is basically a popularity contest, in which each purchase of a book constitutes a vote for it. It is not an absolute measure of sales quantity, but only a relative measure of where one book stands among all others sold on Amazon. Approximate correlations of average Amazon sales rank to U.S. sales can be found both in Aaron Shepard’s Aiming at Amazon and in Morris Rosenthal’s Amazon sales rank analysis. But these are ballpark figures only—especially Aaron’s—and besides, they’re subject to changes over time and season.
Amazon sales rank for all books is now updated once each hour, and all at once. At that time, a book jumps to a higher sales rank (a lower number) for the sale of any new or used copy. With no new sale, the sales rank will drift lower (to a higher number) as books that have sold copies push it down. If a book has no sales rank at all, that means no one has ever bought it!
The time of hourly updating is fairly regular but changes over time and also varies according to your geographical location. For instance, at the Sales Rank Express control center in Washington state, it was found one day to occur regularly at about a quarter after the hour. On the same day, at the Foner Books offices in Massachusetts, it was found to occur on the hour. And on another day here in Washington, it started out at quarter to the hour, then switched later to a quarter after.
The jump in Amazon sales rank that results from a sale will probably not occur at the next hourly update. Tests in May 2007 showed a typical time lag at Amazon.com of around two to three hours between the sale and the jump in sales rank.
Occasionally, Amazon’s system may become “stuck,” so that sales rank does not advance after a sale. You may see sales ranks remain completely static for long periods, or see most of them drift slowly downward. Just wait a while, and Amazon will fix it.
Amazon sales rank is a lot less steady than it used to be, now being subject to wide fluctuations. So, you’ll have to check a book’s sales rank now and then over an extended period to get a good sense of its true position. This, of course, is a weakness of a sales rank checker like Sales Rank Express as opposed to a sales rank tracker with its recording of historical data. But the upside is that you’ll get a better sense of short cycles in book sales.
Also, a sales rank tracker might check sales rank only once a day in the middle of the night, when some books may not sell at their best. Sales Rank Express, by contrast, shows your sales rank as it is right at the moment, in real time.
Updated May 30, 2009