Keywords for books come in three kinds, and most bad keyword advice comes from mixing them up. Store metadata keywords are the phrases you type into your retailer listing (seven slots on Amazon KDP) that decide which searches you surface in. Advertising keywords are phrases you bid on and pay for per click. Discovery keywords are the words readers themselves use when they describe the book they want — which, in fiction, are almost always trope names. The first two are chosen from search volume and competition. The third is chosen from demand: what readers ask for and are not getting. This page covers all three, and gives you the demand numbers for the last one.
These are the phrases in your listing — on Amazon KDP, seven slots, each holding a full phrase rather than a single word. They cost nothing, they are editable at any time, and they are one of the few levers you fully control after publication. Choose them for precision: a phrase you can realistically rank for and that your book genuinely satisfies, because Amazon rewards clicks that turn into reads. The detailed mechanics live on our KDP keywords guide.
Phrases you bid on inside an ad platform. Different economics entirely: here a broad, expensive term can still be worth it if the conversion holds, and a cheap term can be worthless if it brings the wrong reader. This is the one place where a search-volume and competition tool genuinely is the right instrument — Publisher Rocket and its alternatives exist for exactly this job, and we do not compete with them on it.
This is the layer most guides skip. When a reader describes what they want, in a review or a BookTok comment or a forum thread, they do not use category names. They say “enemies to lovers but he falls first”, “forced proximity, one bed, no third-act breakup”. That vocabulary is trope vocabulary, and it is the vocabulary your blurb, your covers, your ad copy and your metadata should all be speaking. We have classified 721,971 such requests, 27,618 of them from BookTok, and the pattern is consistent across every source we read.
Choosing keywords on volume alone. A volume tool cannot distinguish a phrase that thousands of readers search and two hundred books already answer from a phrase thousands search and almost nobody answers. Those two look identical in the tool and are opposite decisions in reality. The separator is the underserved share — how much of the demand behind a phrase the current shelf leaves unmet.
Counted reader requests per trope, how many landed in the last 28 days, and the share our engine flags as unmet by books currently available. A high request count with a high underserved share is a phrase worth pointing a keyword slot at; a high count with a low underserved share is a crowd.
| Trope phrase | Reader requests | Last 28 days | Underserved |
|---|---|---|---|
| enemies to lovers | 11,238 | 327 | 96% |
| forced proximity | 19,019 | 403 | 96% |
| found family | 56,220 | 779 | 97% |
| dark romance | 12,247 | 327 | 96% |
| slow burn | 21,694 | 490 | 98% |
| reverse harem | 9,355 | 215 | 97% |
| grumpy sunshine | 1,940 | 100 | 96% |
| fake dating | 1,767 | 70 | 96% |
| he falls first | 1,107 | 76 | 95% |
| age gap | 2,945 | 111 | 97% |
| hurt/comfort | 3,382 | 200 | 97% |
| second chance romance | 14,160 | 146 | 98% |
Counted 2026-08-21 from 721,971 classified reader requests across 138 demand lanes. Underserved = the share our engine flags as unmet by the books currently on the shelf. These are demand figures, not Amazon search volumes — we do not have search volumes and do not claim to.
The corpus these demand numbers are counted from, as of 21 August 2026.
Counted 2026-08-21 18:49 UTC by direct query against the Tropesmith corpus. Method: how we read reader demand · how a Map is built.
A Tropesmith Map scores your exact trope stack on live demand versus supply — and names the gap you can own.
Build my Map → See a real sample Map first → See pricing →Book keywords are the phrases attached to a book so that a store, a search engine or an ad platform can decide who to show it to. There are three distinct kinds and they are often confused: store metadata keywords (the seven phrase slots Amazon KDP gives you, which shape which searches and also-boughts you appear in), advertising keywords (phrases you bid on, which cost money per click), and discovery keywords (the words readers actually use when they describe what they want, which are usually trope names). They are chosen differently and confusing them is the most common and most expensive mistake.
On Amazon KDP, seven slots - and each slot holds a phrase, not a single word, so 'enemies to lovers hockey romance' is one keyword rather than three. Words already in your title and subtitle are indexed anyway, so repeating them wastes a slot. Advertising keyword lists are not capped the same way; there you are limited by budget and by how many phrases you can actually manage.
Start from what your book genuinely delivers, gather candidate phrases from Amazon's own autocomplete, and then choose between the finalists on demand versus supply rather than on volume alone. A busy keyword and an unmet one look identical in a volume tool. Tropesmith classifies 721,971 reader requests by trope across 138 demand lanes and flags the share of each that the current shelf leaves unmet, which is the number that separates a crowded phrase from a winnable one.
For fiction, they are often the best ones available, because trope names are how readers actually describe what they want to each other. Someone asking for a book on BookTok or in a Goodreads review rarely says 'contemporary romance' - they say 'enemies to lovers, forced proximity, he falls first'. We have read 27,618 reader requests from BookTok alone and the vocabulary is overwhelmingly trope vocabulary.
Yes, and it is worth doing before paying for anything. Amazon's search autocomplete shows real phrases shoppers type. Also-bought rows show adjacency. And the trope demand pages and lane snapshots on this site are free to read with no signup, with the count date on every figure. Paid keyword tools add search-volume estimates and competition scoring on top of that.
Demand figures on this page come from the Tropesmith reader-demand engine, counted 2026-08-21. This guide is general publishing information and is not affiliated with Amazon. Part of the market intelligence hub.