Kindle Spy Review: How Spying On Your Competition With KDSpy Boosts Sales!

KDSpy Review

Kindle Spy Review Summary

Kindle Spyalso known as KDSpy, is a browser extension that Kindle publishers use to reverse engineer the most profitable categories in the Amazon Kindle & paperback marketplace. It also helps discover niche opportunities. KDSpy v5 has helped thousands of Kindle publishers optimize their book title, do proper keyword analysis, and increase their average monthly revenue for their Kindle business.


Quality extension (web based) software that's been around for years and continues to be updated.


You can't beat the 1-time payment price.

This is a One time payment software for just $47!


hether you hate it or love it, competition analysis, keyword analysis, and getting a winning edge are part of the self publishing game.

When I first started self publishing, I only used Kindle Spy (aka KDSpy) as a tool to do niche & keyword research.

Over the years other tools improved on what Kindle Spy does (other tools aren't extensions - so this is a plus for some people), but what wasn't replicated is what I'm going to show you in this article.

Today, I’ll show you how to use Kindle Spy to pick the most profitable categories for your Kindle books. This is by far, the main reason to get Kindle Spy—in my honest opinion.

We'll cover the KDSpy's other bells & whistles (the word cloud, estimated sales data, the competitor tracking feature etc), but the main focus will be on the software's main benefit (category analysis). 

Specifically, the exact step-by-step process for getting the big orange badge next to your books that screams "Click Me."

Before we get to that, let's address how KDSpy is usually used by authors.

How Most People Use Kindle Spy

Note: In my Kindle Spy Review video, I mentioned that I wasn't able to do a tutorial on how to do category analysis. This was because Amazon was split testing the way it displayed the Kindle Best Seller pages which prevented me from doing analysis the way I was used to. However, things are back to normal now and you can use KDSpy to do category analysis in the way shown in this article (keep reading and you'll find the section). 

There are typically 2 ways Kindle publishers mainly use this browser extension tool. However, I'm going to add a 3rd way of using Kindle Spy and that is by utilizing KDSpy's sales tracking feature.

Let's go over the typically ways KDSpy is used now and in the next section we'll cover category analysis—the real power behind KDSpy.

1) Checking the Profitability of A Keyword

For example purposes, let's say I'm looking to publish under the keyword paleo diet

I went ahead and (1) typed this keyword in the Kindle store and  got my page 1 Amazon results. Next, (2) I clicked on the KDSpy Chrome extension:

KDSpy V5 Keyword Analysis

Keyword analysis 

Doing this will give me columns worth of valuable data for each of the top ranking books, including:

  • the # the book is ranked in,
  • the Kindle book title,
  • the page count,
  • the price of the book,
  • estimated sales,
  • the estimated monthly revenue,
  • the amount of reviews per book,
  • and the Amazon Sales Ranking (the closest this number is to #1 the more the Kindle is selling).

Furthermore, you'll notice the bottom-right section of the KDSpy browser extension has a traffic light section:

Kindle spy - somewhat useful features

I don't recommend paying too much attention to the traffic light bubbles.

And the Total Monthly Rev. is a rough guesstimate in my experience.

However, the three traffic light circles: 

  • Popularity,
  • Potential,
  • Competition

can sometimes be good indicators. 

In this case,  "Popularity" for the keyword paleo diet, is red which if you hover over the traffic light bubble with your mouse, will say "Warning: this keyword is not very popular." I doubt that for this keyword, but let's continue.

The second traffic light bubble (green in our case), "Potential," is green. Obviously meaning there's a lot of potential for this keyword.

And the third traffic light bubble, "Competition," is red. An indication that this is a highly competitive keyword.

Yellow can appear sometimes too—basically meaning it's neutral.

Pro Tip #1: Experienced Kindle publishing experts don't publish by the results of these traffic light bubbles. Instead they use tools like KDSpy for keyword analysis.

They self publish books under keywords that have a consistent number of books with Amazon Best Sellers Ranking  under 50,000 AND they create an authority blog or other traffic sources to drive traffic beyond to their Kindle books. 

If you don't use a good book marketing strategy... good luck ranking in an overly competitive keyword without using black hat tactics (not recommended).

So, how does this Kindle Publishing data benefit you?

Here are just a few reasons:

  • you no longer have to manually check each book's sales page for this data - instead KDSpy compiles it in rows & columns for you in it's browser extension dashboard,
  • you can see how the keyword is being used by the competition at a glance,
  • you get a good idea of how profitable a book by checking the average monthly revenue column,
  • it displays the number of Amazon Kindle review so you know how to approach your book review campaign.

The Word Cloud: A Somewhat Useful Feature...

An extra featurethe Kindle Spy browser extension has in its interface is the Word Cloud.

This is what the Word Cloud looks like (it's a hyper-link towards the top-right of the browser extension interface):

KDSpy Word Cloud

Word Cloud in action

The Word Cloud can potentially reveal keywords or keyword variations that you might've missed or never thought of.

It reveals the most-used keywords that authors use in their titles & subtitles.

Well, that was the first way most publishers use Kindle Spy. This first method of using KDSpy is often taught in Kindle publishing courses.

Let's move onto to the second most common way of using KDSpy.

2) "Spying" On Other Authors

Another way I and other successful Kindle publishers use KDSpy is by spying on a competitor's author page.

For this example, let's examines a well-known self publisher's book portfolio: Steve Scott.

KDSpy Competition Analysis

KDSpy v5 shows Kindle book AND paperback book data (see the two tabs in the image above)!

From the image above, we can see that the 80/20 applies here. The majority of his Kindle books sales come from his top 6 books according to his estimated monthly sales. 

None the less, this is an impressive portfolio in the habits niche.

Notice that KDSpy filters Steve's (or any author's) books by lowest (best selling) ABSR to highest ABSR (worst selling). The Sales Rank column is a good indicator of how good a book is selling.​​

Steve's been at this for a few years and is an expert at his craft. He uses his blog, email list, and optimizes for the Amazon search engine to make passive income sales from his books.

His average monthly revenue has surpassed five figures a month. If you decide to follow in Steve's footsteps I recommend taking his self publishing course.

Other things you can draw from this type of KDSpy author analysis is the keywords the author is using in his/her book titles & subtitles.

Depending on the level of competition and the status the author commands... these keywords can potentially open some doors.

(I say potentially because software data is just the tip of the ice berg in Kindle publishing—no self publishing software shows the online marketing funnel that the author may be using in their business).

3) Keep Track Of Your Competitor's Rankings

Another cool feature KDSpy has that no other Kindle software does, is keeping track of other author's book sales rank.

You do this by simply clicking the "T" while you're spying on a potential keyword (or author profile):

KDSpy Other Book Competition Tracking

After you click on the "T" you'll your KDSpy dashboard will switch to this tracking page:

Track Sales Rank of Any Book

Click on the Green "Track SalesRank" button and KDSpy will start tracking your competitor's book sales rank every day and display it on a graph.

KDSpy Tracking Feature Day 1

I find this to be one of Kindle Spy's most valuable tools (after category analysis).

You know a book is making good sales revenue when it's Amazon sales rank is below 100,000. It's even better if it's consistently 50,000 or below!

The image below is an old image of me tracking a competitor's sales rank for 30 days (the new version of KDSpy works just the same). I wanted to see how this book would do after a month's time and KDSpy's sales tracking feature delivered. 


The average sales rank for 30 days of tracking this competitor was 87K.

The sales rank performance of a book in your niche is only part of an equation, but this feature validates there's money to be made in said niche.

When you don't have a tool like KDSpy, you'd have to keep track of how well your competition is doing on a spreadsheet or paper daily... 

I'm not sure about you, but I rather have a software do this type of tracking for me.

When a week has passed, feel free to check on this data graph by visiting your competitor's Amazon sales page and then clicking on the KDSpy extension. You'll find your past 7 days of data waiting for you .


Now tha we've covere the 3 main ways authors & publishers use Kindle Spy, let's get to the good stuff... category analysis!

Why Should You Care About Your Book's Kindle Book & Book Categories?

2 words: more exposure.

Exposure is the name of the game when it comes to Kindle Categories.

I’m going to show you solid reasons why you should choose your categories strategically if you want to leverage the power of Amazon.

#1. An Attractive Orange Badge Next To Your Book

Okay, let me set the scene.

You’re doing some niche research in a cookbook niche and you come across some books on the first page of results and they're doing are doing well.

kindle books with best seller logos

2 out of the 3 books above are clearly stand out more in the image above (even without the red arrows).


best seller logo

The attractive orange “Best Seller” badge that yells "Click me!" to prospective buyers.

The publisher/author who has this a Best Seller badge by their book usually has an upper hand in the rankings.

This simple orange badge leads to higher click through rates for your books and signals to Amazon's algorithm that your book should be ranked higher.

You too can get a Best Seller sticker by being the #1 best seller in your respective category.

For example, the first book in the image above has the following Amazon Best Sellers Rank in the paid Kindle Store:

amazon cookbook is a best seller

and is #1 in its category: Turkish Cookbooks, Food & Wine.

Turkish Cookbook? I thought this was an Instant Pot Cookbook!

Is this a little mischievous? Perhaps. I haven’t purchased the actual cookbook myself and perhaps there are Turkish recipes in the book.

At least it’s not under a sports category or something like that (KDP corrects that these days).

The point is that self publishers use this gray hat tactics to get that push into a semi-competitive yet easier to rank category.

On the other hand, book 3 in the first image above didn’t do the greatest job at choosing his/her category.

He or she probably chose a category that was overly competitive or just didn’t have enough Amazon traffic.

#2. Let Amazon Promote Your Book For You!

Whether you're doing Kindle niche research or just browsing for a book to read – if you happened to search a keyword and clicked through a book in a best selling category you’ve seen Amazon promote a book before.

That’s right, Amazon rewards best sellers with free email advertising.

Here’s an email I received from Amazon after searching for cookbooks:

amazon email

And because Amazon has Facebook pixels installed on their site, they know when you’ve landed on a best selling book's page.

Because of this, you can expect to see some form of Facebook advertisement of that book. Amazon usually places these in the Sponsored area (side widget).

amazon facebook ads

*editor correction: "ads" not "adds"

Enough said, rank 1st in your category and you’ll have good’ol Amazon in your ring corner feeding you sales!

How to Do Category Research With Kindle Spy

Okay, so how does KDSpy help you be the #1 best seller in your category?

For the guide below, we'll do category research for as if we were aiming to get the best seller badge for a cookbook.

Step 1 – Figure Out Your Competitors' Categories

KDSpy Category Analysis Step 1

As you can see the book above has the best seller badge in the category Native American Cooking, Food & Wine and is also ranking #1 for the keyword Instant Pot Recipes Cookbook (at the time of writing this article)​​.

Going to the book's sales page I can see that the book is a best seller in 3 categories. One of them being a book category:​​​​

best seller in 3 categories

At this point, let’s open anyone of these categories up – let’s choose “Native American Cooking, Food & Wine."

We can access this category page by clicking the blue hyperlink above. The page should now display this category in full:

Amazon Best Sellers Demo

As you can see this example book is sitting firmly at the #1 spot for this category's best seller list.

Step 2 – Analyzing Category Pages with KDSpy

KDSpy can analyze the top 20 books and more on any best seller category page - including both Kindle books and physical books (when applicable).

When I click on the KDSpy Google Chrome Extension, this is what I get for our example book category:

KDSpy v5 Category Analysis for Kindle and Books

If you hover over the red "i", KDSpy will tell you how many sales are required in 24 hours to be #1 in the category!

Sales Require to be Best Seller via KDSpy

Notice that KDSpy has compiled all the top 17 books in the category and provides important key performance indicators for the books in this category. 

For instance, the Sales Rank column is a good indicator of how profitable a book is. The more books under 100,000 - the better.

But, things are not as black and white. The more performing books there are in a niche usually means the more competitors there are fighting for that #1 spot.

This is why I recommend to pick adding the maximum number of categories in you KDP dashboard settings. 

Pro Tip #2: if you contact Kindle Direct Publishing, you’ll be able to add 7 more categories to your book's sales page (for a total of 10 Kindle categories). This will increase your chances of achieving best seller status in at least one of your book categories.

I like splitting my categories into two types of categories:

  • 5  Competitive Categories that have an average sales rank of under 100,00 (KDSpy shows you this when analzying categories).
  • 5 Non-Competitive Categories that are not that competitive so I can get the Best Seller badge quicker (these are related niche categories that most authors & publishers would bypass - especially if they didn't know about tip #2 above).

I recommend visiting your competitors' book sales pages and inspecting each of their categories with KDSpy. 

KDSpy will show you the average sales rank, average monthly revenue and more when you do category research:

KDSpy Parent Category Analysis

Analyzing the category above, notice that the Avg. Monthly Rev. and Sales Rank are much better than the prior category, but the competition is strong. You can tell by the Price column.

This category will get your book more traffic to your books, but the chance for you ranking #1 are slim (indicated by the red bubble). Consider adding such a competitive category to 10 category choices.

Starting to see how KDSpy can help you?

Summary On How to Use Kindle Spy for Category Analysis

  1. Benchmark your competitor’s Kindle & book categories.
  2. Run Kindle Spy on your competitors' category  pages and see which ones are doing the best.
  3. Choose 3 categories for your book (competitive or non-competitive at this point).
  4. Do more category analysis with KDSpy for the 7 remaining categories for a total of 10 categories (I recommend 5 competitive & 5 non-competitive categories as explained in the prior section).
  5. Contact KDP to add the 7 remaining categories to your book's sales page (your book must be published before you can do this step).

It’s important to note that not all categories are available to you in your KDP dashboard. This is by design.

Amazon tends to hide a lot of the available categories from publishers.

Don’t worry though, you'll know which categories to request when you contact KDP thanks to KDSpy.

Once your book is live, contact KDP and ask them to add your well researched categories to your book. I usually provide my book’s ASIN in my email to KDP.

They’ll get back to you and your categories should be added shortly!

Alternative Software to KindleSpy

Kindle Spy has made it's mark as one of the best Kindle publishing software on the market. However, you might've heard about two other competitor's. Namely Publisher Rocket (aka KDP Rocket) and Kindle Samurai.

You might've heard about KDP Rocket and you migh be asking which is best when it comes to KDP Rocket vs Kindle Spy.

I recommend both and here's why. Both of these software can do keyword research, category analysis and more.

Yet both have features that the other one can't do.

For example, KDP Rocket can not pull the data from an Amazon's Best Seller page like KDSpy can. KDP Rocket has a category feature, but there's nothing like getting category data on the same browser page. 

This is because KDSpy is a browser extension while KDP Rocket is a desktop software.

Additionally, KDP Rocket can't track a competitor's book sales ranking for and display the data in graph format as shown in this article.

On the flip side, Kindle Spy doesn't display estimated Amazon Searches Per Month of keywords. Which is something that KDP Rocket can do. Kindle Spy also can not do keyword research for Amazon ads.

They are competing software in the Amazon self publishing marketplace, but, as you can see, they're actually different in multiple ways. I use both and am comfortable recommending both.

For more information on this competitor watch my Publisher Rocket review:

Editor's Note: KDP Rocket has changed it's name to Publisher Rocket.

As for Kindle Samurai, I haven't personally used it. It never drew my attention and looks unimpressive. If you'd like me to review it let me know in the comments below.

And if you've used it personally, please share your experience in the comments as I'd be interested to know if it's beneficial to have!

My Honest KDSpy Review


  • Works On Kindle & Paperback Books
  • Continuously Updated & Improved
  • You Can't Beat the Price
  • You Can Track Competitor's Book Sales Rankings


  • Doesn't Display Monthly Amazon Search Volume for Keywords


Kindle Spy is just one of the many tools in my Kindle Publishing tool belt. It’s not going to break or make your self publishing business – no software or tool will.

That being said, KDSpy can give you an upper hand when choosing categories wisely.

Wesley Atkins is the creator of Kindle Spy and I’ve seen some Amazon KDSpy version updates over the years. 

I noticed that he’s on top of any updates that Amazon comes out with which is great because the software draws data from Amazon's API and they're always changing their interface.

You can’t beat the price for the lifetime access browser extension – coming in at a low $47.

It’s easy to install, Mac and PC compatible, and available for Chrome and Firefox browsers.

If you’re looking for a competitive edge and a much better chance of your book(s) getting the best seller badge, I recommend KDSpy.

I hope you found this KDSpy review article informative and valuable.

To your publishing success!


Hey guys, John here. I'm an online marketer who brings back the treasures and truths I find and share them with you right here on my site.