Amazon KDP Keywords and Categories Explained by a Newb

I used to think writing the book was the hard part. Then Amazon showed me seven empty text boxes labeled “Keywords,” and I realized I’d been living a very sheltered life. Categories I could handle—pick the ones that fit your book, add a couple low-competition options so maybe you’ll wake up one morning with a Best Seller tag you didn’t earn yet but will happily take. Easy enough.

Keywords, though? Keywords felt like Amazon quietly asking, “How well do you understand human behavior, search psychology, and the deepest fears of the algorithm?” And then giving me about 50 characters to answer.

The first time I stared at those seven keyword slots, I had the same feeling I used to get when someone handed me a piece of equipment I’d never used and said, “Don’t worry, it’s simple.” Simple is always what people say right before you blow something up.

In this post, I'll discuss some things I've learned so far trying to figure all this out.

Categories: The Part Amazon Actually Made Kind of Easy

Categories are the warm-up stretch of KDP. They’re the part where Amazon pats you on the head and says, “Here, try these first. You can’t mess them up too badly.” And for the most part, that’s true.

When you’re picking categories, you’re really making two decisions:

1. Where your actual readers hang out, and

2. Where you might stand a chance of outrunning the competition.

The first one’s straightforward. If you wrote "Grimdark", don’t put it in “Christian Romance” unless you want some very confused reviews. You pick the categories that genuinely reflect your book. That’s the part every beginner expects.

The second decision is where things get interesting.

Some categories are crowded enough that breaking into the top 100 feels like trying to find parking at Costco on a Saturday. You’re technically allowed to try, but you’re probably going to end up circling the lot while someone else pulls into the spot you were aiming for.

That’s why those more expert than I suggest choosing one or two categories with lighter competition. Not “misleading,” not “gaming the system” — just giving your book a fighting chance to show up on a list where the top three spots aren’t permanently occupied by S-tier authors. The hope is to land a Best Seller tag. Readers notice it, and sales move because of it.

And here’s where tools like Publisher Rocket (and others) actually make life easier. Rocket shows you real data—how competitive each category is, how many sales you’d need per day to rank. It cuts down the blind searching and lets you focus on the categories that both fit your book and give you a practical shot at visibility.

Keywords: Where Good Intentions Go to Die

If categories are the warm-up stretch, keywords are the part of the workout where you question your life choices. Amazon gives you seven keyword boxes, each with a 50-character limit, and somehow expects you to fill them with the perfect combination of search phrases that will unlock the algorithm like a safe.

The problem isn’t the boxes themselves—it’s figuring out what Amazon wants from you. Single words? Phrases? Spells? A blood sacrifice? The documentation isn’t exactly clear.

So I did what any sane person would do: I went looking for people smarter than me.

Kindlepreneur, for example, has an excellent breakdown of how to approach keywords. The article walks through building keyword phrases that reflect how real readers search, while the accompanying YouTube video breaks it down in plain English. Both were helpful, if only because they reassured me I wasn’t completely misunderstanding the assignment.

Reedsy adds a similar perspective but also talks about reader intent and strategies for testing your ideas. The idea is to consider what readers are typing into the search bar when they want a book like yours? That’s the heart of a keyword. They also mention a warning of things not to use that may garner unwanted Amazon attention.

Once you understand the basics, the strategy starts to click:

• Don’t repeat your title or author name; Amazon ignores that.

• Don’t waste space on single words. Use phrases.

• Don’t try to outsmart the algorithm; it has no sense of humor and won’t appreciate your creativity.

• And don’t just throw spaghetti at the wall—your seven boxes are not seven separate universes. They work together.

Of course, knowing the strategy and actually filling the boxes are two different things. This is where Publisher Rocket helped me stay sane. Instead of guessing what readers search for, Rocket pulls up real phrases and shows how competitive they are. It’s basically night-vision goggles for navigating the keyword jungle. Suddenly you can see which terms are oversaturated and which ones your book might have a fighting chance in.

That doesn’t mean Rocket does the work for you. You still have to decide what fits your book and what aligns with how readers think. But sorting through the mountain of possible keywords goes a lot faster when you’re not doing it with a shovel and a flashlight.

By the time I finished my keyword research, I felt like I’d crawled through a tunnel of data and emerged on the other side with seven carefully chosen phrases that might—might—help Amazon point readers in my direction. But I won’t know until the book actually goes live.

Which brings me to the next part: the waiting game.

The Waiting Game: Theory vs. Actual Results

This is the part nobody warns you about. You can spend hours researching keywords, fine-tuning categories, digging through Publisher Rocket, and building what feels like a NASA-approved launch plan—and then you hit “Publish” and suddenly it’s all out of your hands. It’s like sending a kid off to their first day of school: you’ve packed the lunch, tied the shoes, rehearsed the manners, and now you just hope they don’t eat glue.

That’s where I am right now. My book isn’t live yet, so all of this is still theory. Educated theory, yes. Hard-earned theory. But theory all the same.

When the book finally launches, Amazon is going to take my carefully chosen categories and my beautifully optimized keywords and run them through its algorithmic blender. Maybe it works. Maybe it doesn’t. Maybe the algorithm shrugs and wanders off to recommend a gardening book instead. There’s no way to know until the data starts trickling in.

What I do know is this:

• If the keywords don’t perform, I can change them.

• If the categories don’t help visibility, I can adjust those, too.

• If everything crashes and burns, I’ll learn why—and fix it on the next round.

That’s really the heart of KDP: you’re not carving anything into stone. You’re testing, observing, tweaking, and trying again. The platform rewards people who keep learning, not people who get everything perfect on the first attempt. (No one does, by the way. Anyone who says otherwise is lying or selling a course.)

So for now, I wait. And when the numbers start coming in—good, bad, or confusing—I’ll make adjustments. Because that’s the real trick in all of this: treating publishing like a process, not a one-time gamble.

Conclusion: Keep Learning, Keep Adjusting

When I first started digging into Amazon KDP keywords and categories, I treated them like a final exam I had to pass before I could call myself a real author. Eventually I realized they’re just tools to help readers find your book. Not magic. Not destiny. Tools.

If you want to follow the journey—and pick up more lessons from the trenches as I figure out what actually works—I’d love for you to join my newsletter. It’s where I share updates, tips, and the occasional hard-earned insight I pick up while stumbling my way through this publishing adventure.

Thanks for reading, and good luck on your own KDP path. We’re all learning as we go.