# KDSPY review (2026): is it worth $79? > Browser extension for Amazon book category and keyword research Checked Oct 23, 2026 ยท graded Oct 23, 2026 by ToolGPA. KDSPY, once called Kindle Spy, is a browser extension that analyzes Amazon's Kindle, print and audiobook listings while you browse the store. It estimates the sales and revenue behind a category, a keyword or an author's books, suggests related keywords, and tracks the sales rank of chosen books. It is sold for a single payment. - **Category:** Keyword Research Tools - **Made by:** LeadsClick Ltd (trading as Publishing Altitude) (since 2014) - **Website:** https://www.kdspy.com - **Runs on:** Browser extension - **Who should skip it:** Not for you if you want to try it first, as there's no trial or free plan, only a 60-day money-back guarantee. - **Facts last checked:** Oct 23, 2026 ## Pricing As of Oct 23, 2026, KDSPY is a paid product, starting at $79 one-time, plus tax where it applies. - **Pricing model:** Paid - **Free plan:** None. - **Free trial:** None listed. | Plan | Price | What you get | | --- | --- | --- | | KDSPY Pro | $79 one-time | Unlimited use, all future updates and a license for two devices. Shown as reduced from a crossed-out $197, with no end date. | Read from https://www.kdspy.com/ on Oct 23, 2026. Prices change, so confirm with KDSPY before buying. ## Key features - **Category analysis:** Breaks down any of Amazon's 25,000+ Kindle, book and audiobook categories, with each book's key figures and an estimate of what a first-page listing earns. - **Sales needed to rank:** Estimates how many copies a book has to sell in 24 hours to reach positions 1 to 20 in a category. - **Keyword analysis:** Gives a keyword's revenue potential, the number of competing books and how likely a new book is to rank, with A-Z suggestions that export for Amazon Ads. - **Author and publisher lookups:** Summarizes an author's page in one click, with sales rank and projected revenue for each Kindle, paperback, hardcover and audiobook edition. - **Book tracking:** Follows the daily sales rank of any number of books for 30 days and charts their estimated daily and monthly revenue. - **ChatGPT prompts:** KDSPY Insights builds prompts about a category, keyword or competing book to run in ChatGPT, across eleven report types. ## Good for - Self-published authors choosing a book topic, category or keywords - Authors who want to research while browsing Amazon itself - Buyers who prefer one payment to a subscription ## Worth knowing - It runs only as a browser extension for Chrome, Firefox, Edge, Opera and Brave; the site says it does not work on iPads, tablets or phones. - Data covers Amazon only: the US, UK, Canada, Germany, Australia, Italy, Spain, France, India, Japan, Mexico, Brazil and Poland stores. - There is no free trial or free plan, only a 60-day money-back guarantee. - The license covers up to two devices you own. ## ToolGPA grades **GPA: 2.2 out of 4**, graded Oct 23, 2026. KDSPY is a browser extension that estimates the sales and revenue behind Amazon book categories, keywords and authors as you browse the store, and tracks the sales rank of books you pick, for $79 once. But the sales figures are its own estimates, it covers Amazon only, it runs only in a desktop browser, and there's no trial, just a 60-day refund. - **Value for money: A.** $79 once, with unlimited use and future updates, well under a year of this category's $17 middle subscription. The page shows it cut from a crossed-out $197, with no end date, and tax is added where it applies. - **Free plan and trial: F.** Nothing is free: no free plan and no trial. A 60-day money-back guarantee is the only safety net, and that isn't a trial. - **Features: C.** Breakdowns of 25,000+ Amazon book categories, sales needed to rank, keyword revenue and competition with A-Z suggestions, author lookups, 30-day rank tracking and ChatGPT prompts. It does Amazon book research fully, but that's a smaller job, and sales and revenue are its estimates. - **Ease of use: B.** No rating on record. It's a browser extension that works on Amazon's own pages as you browse, with no accounts to connect. - **Platforms and integrations: C.** An extension for Chrome, Firefox, Edge, Opera and Brave on a computer, and the site says it doesn't work on iPads, tablets or phones. Its only link elsewhere is prompts it builds for ChatGPT. These are ToolGPA's own grades. Graded from this listing, whose facts were read from KDSPY's own pages on 23 October 2026. Not based on using the product, and shorter than our full reviews. ## Where it stands among keyword research tools - KDSPY's GPA of 2.2 is higher than 12 of the 51 other keyword research tools we grade, and level with 10. - It stands best on value for money (A, above 37 of 51) and worst on free plan and trial (F, above 0). The category's chart of price against score: https://toolgpa.com/charts/keyword-research ## Keep it, or make your own? **Keep it.** To replace KDSPY you would be making search volumes for millions of keywords, gathered and kept up to date. That is not a weekend's work, with an AI app builder or without one. That makes this kind of software worth paying for, not this one in particular: 29 of the 51 other keyword research tools grade higher. It costs $79, paid once. - You could not: Search volumes for millions of keywords, gathered and kept up to date. - You could not: Data from Amazon's seller tools and years of sales estimates. A judgement by ToolGPA from this listing, by rules that are the same for every tool. Nothing was built to test it. ## Works with ChatGPT **Tags:** Keyword research, Amazon selling, One-time purchase ## Alternatives - [Publisher Rocket](https://toolgpa.com/tools/publisher-rocket): Amazon keyword, category and ad research for book authors. [Compare](https://toolgpa.com/compare/kdspy-vs-publisher-rocket) - [MerchantWords](https://toolgpa.com/tools/merchantwords): Amazon keyword research from searches made on Amazon marketplaces. [Compare](https://toolgpa.com/compare/kdspy-vs-merchantwords) - [Helium 10](https://toolgpa.com/tools/helium-10): All-in-one Amazon seller suite for research, listings, ads and profits. [Compare](https://toolgpa.com/compare/helium-10-vs-kdspy) ## Sources The prices, plans, platforms and features above were read from these pages on Oct 23, 2026: - https://www.kdspy.com/ Page: https://toolgpa.com/tools/kdspy Listed by ToolGPA (toolgpa.com).