Amazon keywords are often called hidden keywords.
When you sell on Amazon, you can optimize your product by adding keywords to your Amazon listing.
These words do not appear on your Amazon product page, but they will hopefully appear when customers use search queries to find what they are looking to purchase.
Searches on Amazon work in a similar way to search terms on Google or Bing. You need to find relevant keywords to attract the attention of a buyer.
How do Amazon keywords work?
When you assign keywords to your product or book, they may appear in the Amazon search bar. Well, that is your aim when you add keywords.
Keyword optimization on Amazon is similar to search engine optimization (SEO).
You want to find long-tail keywords, which are short phrases, for your product or book.
These work along with your product title, but you can’t see them in your product description. That is why they are called hidden or backend keywords.
They will only appear when a buyer uses the Amazon search bar. If one of your keywords works well, it will appear in the search results.
But unlike Google or Bing, Amazon autocomplete populates the results in a dropdown list.
This makes Amazon SEO a little bit different. You are looking to find keyword suggestions that will populate from your one or two word seed keyword.
If I was trying to sell running shoe or clothes, I would see a result like this when I enter running.
You can see that the results are for shoes, clothes and perhaps a book or a movie.
But if I add shoes to the search, the results change.
Now the results are only related to running shoes.
Search terms work the same way for products and books.
For book keywords, you need to find seed keywords that you can expand to appear in search results.
For example, cozy romance could be extended to cozy romance happy ending.
Every Amazon seller can add keywords. But there is a difference between how you add product keywords and KDP keywords for books and Kindle ebooks.
Character limits for Amazon keywords
For Amazon product listings, there is only one keyword field.
It has a limit of 250 bytes, which is about 250 characters.
You add all your keywords in a string with spaces between words.
Here is an example that Amazon provides for a kitchen chopping board.
Amazon gives a detailed explanation of how-to and how not to use keywords for product pages in its Seller Central help pages.
It includes useful tips about avoiding stop words such as a, also, an, and, any, are, as, at, be, because.
You will also find good advice about certain subjective words and temporary words that you shouldn’t include in your keywords.
If you are an author or publisher, these points also relate to your book keywords.
So it is wise to understand what you can and cannot use in your selection.
For books and ebooks, there are seven keyword fields.
If you are self-publishing, you will be familiar with the seven keyword entry fields.
You can see them in your book details section from your KDP dashboard.
For Amazon book, KDP, and Kindle keywords, there is a 50 character limit.
Look at the keywords that you have for one of your books. How many characters do you use for each of your seven keywords?
How many of your keywords get close to 50 characters?
Also, as I noted above, are you using any stop words in your keywords?
Look at these long-tail keyword ideas for a spy novel.
See how they expand towards the limit, but without using any stop words such as prepositions, articles, or auxiliary verbs.
spy thriller -12 characters
espionage spy thriller -22 characters
world war two espionage spy thriller – 36 characters
world war two true story espionage spy thriller – 47 characters
world war two true stories espionage spy thriller – 49 characters
You can see that there is a big difference between the first and last suggestion.
Should you use more characters?
If you are using short one, two, or three word keywords, will longer ones work better for you?
Do you get more indexed keywords from Amazon? Does Amazon use variations of your keywords?
These are good questions, and there are answers.
Dave Chesson from Publisher Rocket conducted an extensive test on using longer keywords up to 50 characters.
It’s a long read, but you should read the article if you are new to keywords for books.
But if you want to go straight to the answer, then yes.
The more characters you use for your keywords, the more indexed keywords you will get for your book.
Your only challenge now is to find longer keywords.
How to find new keywords
There are many Amazon keyword tools.
The most obvious choice is to use the Amazon search bar.
As in the images above about running shoes, you can use the autocomplete suggestions to build a list of potential keywords.
However, you are restricted to only ten results per search.
You can also use Google.
When you search for a keyword phrase, look down at the bottom of the first search results page, and you will see eight related search phrases.
You can refer to our earlier article on how to find Kindle keywords for free for more ideas and detailed instructions.
But if you are looking for the most effective way to find real-time data on search phrases and keyword usage by Amazon customers, you will need specialized software.
The most popular tool for self-publishing authors and small press for KDP keyword research is Publisher Rocket.
With it, you can access real keyword data without any restrictions.
Is longer better?
Yes, it would seem so.
If you are currently using keywords for your books that are only ten or twenty characters long, it could be a good time to reassess your selections.
Look at what you are using now. See if you can extend them as in the example above for a spy novel.
It is not difficult at all to lengthen your keywords out to close to 50 characters.
But be careful not to use stop words as you extend and don’t use any words that are in your book title and sub-title.
The best part about Amazon keywords is that you can try, experiment, change, and update them at any time.
There is no restriction on how many times you can make changes.
One last tip. You could also take another look at your book description. Does it contain any of the important keywords that you would like to rank?
You don’t want to keyword stuff your description. But you can add one or two naturally in your book description text.
Keywords for books is always work in progress. So anytime you decide to check and revise them, it is always time well spent.