Publisher Rocket
•Target Audience: Specifically built for authors (KDP).
•Pricing: $199 one-time payment for lifetime access (as of Feb 2026). 30-day money-back guarantee.
•Key Features:
•Keyword Search: Finds profitable Amazon keywords, showing search volume, competition, and estimated earnings.
•Competition Analyzer: Spies on other authors’ sales, rankings, and strategies.
•Category Search: Helps find the best of Amazon’s 19,000+ categories to rank as a bestseller.
•AMS Keyword Search: Generates keywords for Amazon Advertising.
•Pros: Affordable (one-time fee), author-centric data, easy to use, covers multiple international markets (US, UK, CA, etc.).
•Cons: Desktop software (needs installation), data is specific to books only.
Helium 10
•Target Audience: General Amazon sellers (FBA), but increasingly used by high-volume KDP authors.
•Pricing: Subscription-based. Platinum ($99/mo billed yearly, ~$129/mo monthly), Diamond ($279/mo billed yearly, ~$359/mo monthly).
•Key Features for Authors:
•Cerebro (Reverse ASIN): Find exactly which keywords a competitor’s book is ranking for.
•Magnet: Broad keyword research tool with massive data.
•X-Ray (Chrome Extension): Real-time data on search results pages (estimated sales, BSR).
•Listing Builder / Scribbles: Helps write keyword-optimized titles and descriptions. AI-assisted copywriting.
•Frankenstein: Keyword processor to clean up large lists.
•Pros: Extremely deep data, web-based, powerful AI tools for listing optimization, useful for “writing to market” by identifying gaps.
•Cons: Expensive (monthly subscription), steep learning curve, many features are overkill for simple ebook authors.
Comparison for “Writing Ebooks”
•Publisher Rocket is better for market research and metadata optimization (keywords/categories) at a low cost.
•Helium 10 is better for advanced competitive intelligence and listing copywriting (using Listing Builder/Scribbles) if the author has the budget.
•Helium 10’s “Writing” Help: It doesn’t write the content of the book, but it helps write the sales page (listing) to ensure it ranks for the right keywords.