Tracking

Sales Rank Charts are Misleading: Here’s a better way to interpret rank across product categories.

If you’ve sold on Amazon for any length of time, you’ve most likely stumbled across Sales Rank Charts that break down rank across a variety of categories.  In today’s post, we’re going to show you why these charts are incredibly misleading, and how you can do your own research to build a proper rank chart to help you make smarter scouting decisions.

Here is one of the popular rank charts, which can be found over at fulltimefba.com:

Sales Rank Chart from Full-Time FBA

Side note: I’m not trying to throw shade or pick a fight with anyone who posts these rank charts.  They are helpful in that they show the relative size of the various categories, but they are misleading when it comes to picking sales ranks targets when you’re scouting in the field.  Let’s dig in a bit and figure out if there’s a better way to build a rank chart (spoiler alert:  there is!).

First off, the Total Items in each category is misleading becuase it includes ALL items, not just the ones that have ever sold.  In the Books category, the chart indicates that there are a whopping 62 million items listed.  While this is true, a better metric would be books that have ACTUALLY sold a copy on Amazon, which would be closer to the 25 million range.  Each of the other categories is similarly overstated because there are millions of items listed on Amazon that have never ever sold even a single copy.  They don’t call it “the everything store” for no reason!

Secondly, the chart leads you to believe that items in the same Percentile across various categories are roughly equivalent.  If you look at the top 5% of books, the rank is 3.1 million.  If you compared this to the Movies & TV category, you might conclude that DVDs with a rank of 68,000 would sell just as often as books ranked around 3 million.

Unfortunately, this is not an apples to apples comparison.  Not even close!  Here’s why:

A book ranked 3.1 million last sold a copy roughly a month ago.

A DVD ranked 68k last sold a copy roughly 5 days ago.

And yet both items are in the top 5% of their respective categories.  Why is there such a difference?

The challenge here is that each category on Amazon sells a vastly different quantity of unique items in a given period of time, which means that a product ranked 100k in one category is usually different than a rank of 100k in another category.

If an item hasn’t sold in the past month, its current rank indicates how many UNIQUE other items within the same product category have sold over the past month.  Some categories are extremely long tail, such as books, while other categories don’t sell nearly as many high-ranked items in a month, such as DVDs.

Now that we’ve poked holes in the Sales Rank Charts, let’s examine a way to build a chart for each category that can help you when doing retail arbitrage.  Since most of our audience deals with media products, we’ll compare books to DVDs (technically the Movies & TV category, but we’ll call it DVDs from now on in this article) for this analysis.  The principles that we’ll outline will work for ANY CATEGORY on Amazon, so if you want to find the key rank benchmarks for another category, simply follow the steps below.

Step 1:  Determine the baseline rank when an item sells a single copy

This step requires a bit of trial and error to find a decent test case, but the effort will be worth it.  You’ll want to find a product that is selling occasionally, not every single day.  When you find a product that fits the bill, take a look at the Keepa chart to see where the rank typically drops to immediately after a sale.  For the Books Category, here’s what this looks like:

Baseline Amazon Sales Rank Chart by Keepa

When an item sells, the rank drops.  Every hour that it doesn’t sell again, the rank drifts up and up until it sells and drops down.  What we’re looking for is the lower level of these rank drops, or “icicles”.  In the Keepa chart above, the lower limit is close to 100k.  If you pull up a number of other books, their charts will show similar drops into the 100k range.  It’s important to note that for higher-ranked items, Keepa doesn’t track their ranks every hour.  So you may see cases where a book ranked 5 million will sell a copy and drop down only to 250k.  This just means Keepa didn’t ping that title every hour, and likely missed the bottom of the rank icicle.

For books, the baseline rank is roughly 100k.

For DVDs, here’s a good example to establish the baseline rank:

DVDs Baseline Sales Rank Chart

You can see that the rank icicles drop to roughly 20k every time a sales is registered.  Thus, a rank of 20k for a DVD is roughly the same as a rank of 100k for a Book.  Items under these ranks are selling often, and items above these ranks are selling less often.  Now it’s time to lock in other key ranks for each category.

Step 2:  Establish benchmark ranks for various lengths of time

Once again, this step may take a bit of trial and error.  You’ll want to dig up some long tail items in your chosen category, to establish the key ranks at one week, one month, three months, and six months.  This will help you build a framework for interpreting high ranked items in each category.  You can pull up random items on Amazon to find test cases, or scan in items around the house.  Once you find an item with a fairly high sales rank, you’ll be in business!

Here’s the Keepa chart for a long-tail Book:

Keepa chart for long-tail book

ne week after this book sold a copy in late August, the rank has already jumped back up to just over 1.5 million.  One month after this rank drop, the rank has risen up to 3.2 million.

Here’s another Keepa chart which shows similar results:

Long-tail sales rank chart

At one month, the rank is up to 3.6 million.

At three months, the rank is at 5.7 million.

At six months, the rank is at 6 million.

If we were to list the benchmark sales ranks for Books, it would look something like this:

under 100k:  selling often, likely more than once a day

100k:  sold within the last hour

1.5 million:  sold roughly one week ago

3.5 million:  sold roughly one month ago

5.5 million:  sold roughly three months ago

6 million:  sold roughly six months ago

It’s important to note that these benchmarks are general figures (or as my finance friends are fond of saying, they’re “directionally accurate”).  Each book will be slightly different, since rank has a memory.  A book that has only sold once in the past year will see its rank drift higher more quickly than a book that is selling a few times a year.  As general guidelines, however, these benchmarks will serve you quite nicely when you come across books when scouting in the field.

What about DVDs?  Let’s find a long-tail item to analyze:

Long-tail dvd sales rank chart

After one week, the rank is up to 100k.

After one month, the rank is up to 150k.

Another long-tail chart will help us gain perspective on longer time frames:

Another long-tail dvd sales rank chart

After three months, the rank is up to 500k.

After six months, the rank is approaching 600k.

To summarize DVDs, the benchmark chart would look like this:

under 20k:  selling often, likely more than once a day

20k:  sold within the last hour

100k:  sold roughly one week ago

150k:  sold roughly one month ago

500k:  sold roughly three months ago

600k:  sold roughly six months ago

Step 3:  Putting it all together

Now that we’ve established the benchmark ranks for Books and DVDs, it’s time to build a scouting strategy.  In general, the more often an item is selling, the lower the profit level you should be willing to accept.  Items that sell quickly are more likely to sell at their current prices, which minimizes the risk of buying the item to flip it.

The less often an item sells, the higher the profit level you should be targeting, since it’s more risky to sit on it for a longer length of time.

When you scan a DVD that has a rank of 80k, you can be reasonably certain that it last sold a few days ago, and you can tolerate a lower profit target since it’s somewhat likely to sell again in the near future.

When you scan a DVD that has a rank of 250k, it likely hasn’t sold in about two months, which means your target profit should be higher.

Step 4:  Applying these principles to other categories

Now that you have a system in place to establish the baseline rank and benchmark ranks for each product category on Amazon, you can apply these steps to additional categories.  If you source toys quite often, you’ll want to build out these benchmark ranks so you know roughly how long ago a toy ranked 100k last sold.  Over time, each category’s benchmarks will become second nature to you and you’ll be able to make better decisions more quickly.

Thanks for reading this lengthly article!  If you found value in it, consider sharing it with someone else who would benefit from the knowledge.

Related Posts