Reference — Kindle Category Opportunity
Competition snapshot for the Science & Math best-seller list, ease-of-entry score 49.5/100.
Category metrics
Score
49.5
Median reviews
623.5
Weak share (top 20)
35%
Median price
$9.99
Median star rating
4.6
Books scanned
50
Worth writing in?
The Reference list shows real reader demand with room left for newcomers: the median book carries 623.5 reviews, yet 35% of the top 20 still sit under 100 reviews. 2 top-15 books hold fewer than 100 reviews at $0.99–4.99 — classic self-publishing breakout books. Ease-of-entry score 49.5/100.
Breakout books — top 15, under 100 reviews, $0.99–4.99
Best-seller list on Amazon| # | Title | Star | Reviews | Price |
|---|---|---|---|---|
| 13 | DSM-5-TR Desk Reference Diagnostic Criteria Guide: A Pocket Companion for Quick and Accessible Diagnostic Information | 4.0 | 38 | $2.99 |
| 12 | The Science Book: From Darwin to Dark Energy, 250 Milestones in the History of Science (Union Square & Co. Milestones) | 4.5 | 76 | $1.99 |
High-frequency phrases in this category's titles
Mine all categoriesHigh-frequency phrases mined from the 50 best-seller titles on this category's list. The ease-of-entry score tells you how winnable the category is; these title phrases tell you which words readers search with — use the two layers together. Frequency is a title statistic, not a search-volume estimate.
| Phrase | Titles | Rank-weighted score |
|---|---|---|
| scientific american | 3 | 140 |
| medical terminology | 3 | 100 |
| healthcare professionals | 2 | 68 |
| understand medical terms | 2 | 67 |
| human body | 2 | 57 |
| life and death | 2 | 30 |
| works the facts | 3 | 26 |
| facts visually explained | 2 | 13 |
| works the facts visually | 2 | 13 |
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More Science & Math categories
1 subcategories under this category
| Subcategory | Score | Median reviews |
|---|---|---|
| █████ | 53.5 | 11 |
Subcategory names are visible after sign-in — a free account unlocks every subcategory score.
Sign up free to unlockCheck the keywords before you write
Category scores show where entry is easiest; keyword lookups show whether readers actually reach for it. A free account includes keyword competition lookups plus unlimited category scans.
After you publish: why aren't readers buying?
Category research picks the direction; review diagnosis reads the readers. The same platform clusters a book's critical reviews into severity-ranked root causes, each anchored to verbatim quotes — see it applied to a full narrative-history title.
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Research snapshot scanned on Oct 19, 2026. Refreshed periodically — not live tracking.