How to Research a Kindle Niche: A Step-by-Step Method with Real Amazon Data
A niche is a group of readers and the books they already buy, and on Amazon it shows up as a best-seller list. Researching it means answering four questions before you write: do people buy here, how hard is it to get in, are new books getting in, and what price works. Each step below shows how to check it for free on Amazon, and what KDPTop measures for you.
1. Start from a best-seller list, not a single word
Every Amazon category has its own Best Sellers top 100 and a New Releases list. Find the narrowest category your book honestly fits: on Amazon, open Best Sellers in Books or Kindle Store and click down the category tree. Narrow lists are easier to rank in than broad ones, and KDP lets you choose 3 categories per book.
KDPTop tracks the top 100 of more than 10,000 categories: big categories every 3 hours, mid-level daily, the long tail about every 3 days. The KDP categories list shows each one with its price band, review barrier and opportunity score.
2. Check demand: do books here actually sell?
Free method: open the books ranked around #20 to #50 on the list and look at Best Sellers Rank on each product page. The lower the rank, the more copies it sells. If even the middle of the list has weak ranks, the whole niche sells little. Then type your topic into Amazon search with the Books department selected and note the suggestions that drop down; they show what readers actually type.
KDPTop turns each book's BSR into an estimated daily sales figure and gives the median for the list, plus monthly search volume for keyword phrases. These are estimates, not Amazon's own sales numbers.
3. Check the review barrier: how hard is it to get in?
Free method: write down the review counts of the top 20 books. If most have thousands of reviews, a new book will struggle to look credible next to them.
KDPTop shows the median review count of the whole top 100 and the share of books with fewer than 100 reviews. A low median and a high share under 100 mean newer books are already competing there.
4. Check whether new books get in
Free method: open the category's New Releases list next to its Best Sellers list and count how many titles appear on both. If the best-seller list is all old titles, readers there stick with what they know.
KDPTop measures the new-release share (books in the top 100 that have been on a New Releases list in the last 90 days) and lists breakouts: new books that reached Best Sellers soon after release.
5. Check the price band
Free method: note the prices of the top 20 and look at the middle of the range, not the extremes. Pricing far below the band can signal low quality; far above it needs a reason.
KDPTop shows the middle 50% price range and the median for every list, with paperback and Kindle kept apart.
6. Decide: go, watch or crowded
Put the four answers together. Real demand, a review barrier you can reach and new books getting in point to a niche worth entering. Strong demand with a wall of reviews is crowded. A list where almost nothing sells is small, however easy it looks.
KDPTop's decision card does this for a category: a verdict (Go, Watch, Crowded or Skip) with the reasons and numbers behind it. The free plan opens one full card a day.
Example: today's numbers for 8 niches
KDPTop data as of 2026-11-11. Daily sales are estimates from BSR, not sales figures published by Amazon.
| Niche | Median price | Median reviews | Under 100 reviews | New release share | Median est. daily sales | Verdict |
|---|---|---|---|---|---|---|
| Cozy mystery | $5.99 | 1,667 | 18% | 49% | 24 | Watch |
| Romantasy | $7.99 | 39,962 | 3% | 23% | 86 | Crowded |
| Adult coloring books | $9.99 | 1,147 | 13% | 9% | 16 | Go |
| Large print word search | $9.99 | 295 | 32% | 18% | 9 | Go |
| Kids coloring books | $7.20 | 1,509 | 7% | 8% | 17 | Go |
| Gratitude & guided journals | $11.98 | 694 | 27% | 13% | 3 | Watch |
| Dark romance | $5.99 | 1,984 | 10% | 61% | 44 | Watch |
| Picture books: feelings | $9.12 | 4,574 | 4% | 5% | 20 | Crowded |
How to read it: low median reviews, a high share under 100 reviews and a high new-release share mean new books are getting in. If estimated daily sales are very low, the niche won't sell much however easy it is to enter.
Common questions
Can I research a Kindle niche for free?
Yes. Amazon's Best Sellers and New Releases lists, the Best Sellers Rank on each product page and the search suggestions are all free. They take longer because you collect the numbers by hand. KDPTop's free plan also opens one full category decision card a day.
What is a good review barrier for a new book?
There is no fixed number. Compare the median reviews with similar lists: a few hundred is very different from tens of thousands. A high share of books under 100 reviews is the clearest sign that newer books are getting in.
How accurate are BSR sales estimates?
They are estimates. Amazon does not publish sales; tools convert Best Sellers Rank into sales with a model, so treat them as a way to compare lists, not as exact sales or income.
Sources
Related: KDP Keywords and Categories: How to Fill the 7 Keyword Boxes and Pick 3 Categories · KDP research tools compared
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