Amazon has various ways of ranking products, but one of the least understood seems to be the Amazon Bestsellers Rank (also known simply as 'Sales Rank'). This post will hopefully help you understand , as a customer, which books are selling well in a certain topic, and as a seller, which products may be your main competitors.

As a seller (or in the case of books, as an author) is your marketing is working? Armed with Amazon's "secret recipe", you also become a better buyer.

Please bear in mind that Amazon does not explicitly state how the Bestsellers Rank is calculated. The information below is based on research, deduction, and processes of elimination.

What is the Amazon Bestsellers Rank?

In all book categories (including Kindle paid and free books), as well as most product categories on Amazon, if you scroll down the page to the 'Product Details' section, you'll see it says 'Amazon Bestsellers Rank'. This is a number that's purportedly calculated hourly (as stated by Amazon) and is linked to the number of recent sales of the product (while also taking into account historical sales data), relative to the other products in that category.

The rank for one product can, of course, be different on different Amazon stores, as each store represents a different 'market' per se. For example, The Monk Who Sold His Ferrari is #17 in the Indian store, while #9,168 in Amazon.com.

A rank of #1, therefore, means that product has recently sold more than any other product in that category, on that store.

AmazonSalesRank1

With this in mind, let's take a look at what we should understand by this ranking. As mentioned above, this Bestsellers Rank is available for most products available on Amazon, but I'll explain this topic mainly using books as a case in point.

The rank is based on sales, not reviews or ratings.

Amazon Books

A common misconception about the Bestsellers Rank is that it takes into account more than simple sales, but it seems this idea is completely untrue.  This rank takes into account only sales (recent and historical, more on this later), so I'm afraid getting tons of Amazon Vine members to leave you tons of reviews and ratings won't necessarily help your Bestsellers ranking.  This means that a rank is not representative of cumulative sales (or overall sales volume), but more on how a product has been selling very recently compared to others in it's category.

That being said, although reviews and ratings have no direct bearing on a Bestsellers Rank, they are likely to influence people to buy your product, and thereby indirectly help your Bestsellers rank.

Sales of  a product don't have an immediate effect on Sales Rank

According to Amazon, the Bestsellers Rank is calculated hourly, but sometimes there is a lag between an increase in sales, and an improvement in a ranking. This lag is usually no more than 2 or 3 hours, but there is some debate over exactly how many product rankings are calculated hourly. This article on WebProNews, mentions that, in the books category, only the top 10,000 books are calculated hourly, whereas books with a ranking of 10,000+ are calculated once per day with 'current projections as well as historic sales information play[ing] a key role in calculations'.

 Books are weighted the same, whether free or paid

amazon-bestseller-rank05

Contrary to belief, paid and free books on Amazon are weighted the same when it comes to the Amazon Bestsellers rank, but are treated differently (in that they have separate bestseller lists).

As mentioned, all that counts is the number of sales relative to other products within the same category. Amazon splits 'paid' and 'free' books into separate categories, so these act as sub-sub categories, in turn having their own bestsellers rank, which seems to be ranked using the same (or very similar) algorithm to paid bestseller ranks.

"However, probably fueling the confusion, Amazon’s Popularity Lists are influenced by price. Free books are worth roughly a tenth of a paid book," ~ Ryan Casey

An increase in sales doesn't necessarily mean an improved ranking

Amazon Books & Sales

As the Amazon Bestsellers Rank is relative to other products in a category, an increase in sales alone isn't enough to increase rankings. To increase the Bestsellers Rank, your product must sell more units than other products in your category. This means that if there's a sudden influx in overall sales in Juicing Machines, and everyone in that category starts to sell more products, the sellers may not see jumps in their Bestsellers Rank, as they might have hoped.

Along similar lines, if your product is selling a steady one unit per day, but some of your competitors start to sell more than you, then your rank will fall (i.e. the number will get higher), even if your sales remain steady.

Predictive features are also built into the algorithm

Amazon Algorithm

Recent sales alone are not all that's taken into account. Amazon also has predictive features built into the Bestsellers Rank, which are likely to be based on historical data of a product. This is how a newly released book can have a higher ranking than a book released three years ago, even when the latter has more cumulative sales- Amazon can predict that the new release will overtake that book in a given period of time.

What this also means is that a book that's ranked 800,000 can see it's rankings skyrocket to 200,000 just with a couple of sales. As you move up the ladder, however, Amazon's complex algorithm kicks in soon thereafter making it harder for you to break through the 100,000 milestone, and even harder to get past 10,000. This is because these higher rated products have historical data to back them up, so a lull in sales for them won't result in as dramatic a drop in rankings as it would for a new product with less data to draw on. In all, the ranking seems to be somewhat logarithmic.

A high-profile, quick launch is short sighted

When it comes to ranking highly on the Amazon Bestsellers lists, as the ranks are based hourly (or daily if the above information is correct), then a quick spike in sales due to a successful marketing campaign, followed by a lull in sales a couple of days later will only serve to see the product's rankings quickly plummet. It's far better to space out a product launch over a period of week, so Amazon can collect consistent historical data to make predictions on future sales. This will thereby make it easier for you to break into higher spots on the ranking table in future.

To learn more about what it takes to get to =1 on Amazon's Bestsllers rank, see the below video.

The numbers speak for themselves

Amazon bestseller

In December 2013 Theresa Regan posted the following figures on her blog representing how many sales we can expect a book to be achieving, depending on its overall sales rank. Of course, these numbers are likely to be rather arbitrary, but they're interesting nonetheless. Note, these numbers do not apply to product categories other than books. It's also important to mention again that it's the sales that cause the ranking. The ranking doesn't cause the sales.

Amazon Best Seller Rank 50,000 to 100,000 - selling close to 1 book a day.

Amazon Best Seller Rank 10,000 to 50,000 - selling 5 to 15 books a day.

Amazon Best Seller Rank 5,500 to 10,000 - selling 15 to 25 books a day.

Amazon Best Seller Rank 3,000 to 5,500 - selling25 to 70 books a day.

Amazon Best Seller Rank 1,500 to 3,000 - selling70 to 100 books a day.

Amazon Best Seller Rank 750 to 1,500 - selling 100 to 120 books a day.

Amazon Best Seller Rank 500 to 750 - selling120 to 175 books a day.

Amazon Best Seller Rank 350 to 500 - selling175 to 250 books a day.

Amazon Best Seller Rank 200 to 350 - selling 250 to 500 books a day.

Amazon Best Seller Rank 35 to 200 -selling500 to 2,000 books a day.

Amazon Best Seller Rank 20 to 35 - selling 2,000 to 3,000 books a day.

Amazon Best Seller Rank of 5 to 20 - selling3,000 to 4,000 books a day.

Amazon Best Seller Rank of 1 to 5 - selling4,000+ books a day. 

Conclusion

There are plenty of other bestseller lists and rankings which you can base your book buying decision on, but Amazon's Bestsellers Rank is by far one of the most cited. As mentioned at the start of the article, though, it's difficult to pin the Amazon Bestsellers Rank down too firmly, but the above is what I've dissected from plenty of research online. People will disagree to an extent with some of the above, but the importance you place on this ranking algorithm is up to you. I don't know how (or even if at all) this ranking impacts buyer decision, but I hope you've found this interesting.

What else do you know about the Amazon Bestsellers Rank (Sales Rank) which isn't mentioned above?

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