Amazon Book Optimizer

What this optimizes

• Browse categories — with the exact picker paths. The biggest single lever, and the most common silent killer: a nonfiction book sitting in a fiction browse tree gets shown to novel buyers against the heaviest competition. Suggestions come from a full copy of KDP's real category picker (about 8,000 paperback and 10,000 Kindle placements), so every path you're given exists and can be selected exactly as written.
• Title and subtitle as keywords — on Amazon these are your search terms, in the genres where buyers search that way. Phrases a buyer would type get found; index-heading phrasing doesn't. Picture books and literary fiction are judged by their own conventions instead.
• The 7 keyword slots — invisible on the product page, so you get a replacement set written to the same rules our own generator uses: buyer-typed phrases, proper nouns where the subject has them, seven different intents rather than one idea restated.
• Series — a standalone book has no flywheel. Books in a series pull readers from every sibling through also-boughts and read-through.
• Cover at thumbnail size — the model looks at your actual cover and judges whether it signals its genre and stays legible small, because that's the size buyers really see.
• Price band — Kindle pays 70% between $2.99 and $9.99, and 35% outside it.
• Rank arithmetic — charting inside a category while invisible overall means the categories are too small to matter. That reads as "no marketing" and is actually a settings problem.

No promises about sales or rankings: everything here is checkable against your own listing. And when the truthful answer is that no metadata change will save this particular book, the tool says that too — that answer is worth more than a polite one.