Amazon BSR Royalties Terms Explained: Complete KDP Dictionary
Key Takeaways
- ✓BSR under 50,000 in most categories indicates consistent daily sales, while BSR over 500,000 suggests minimal sales activity
- ✓70% royalty rate applies to ebooks priced $2.99-$9.99 in KDP Select territories, dropping to 35% outside this range
- ✓ACoS (Advertising Cost of Sales) above 50% typically indicates unprofitable Amazon ads campaigns for most KDP publishers
- ✓KDP Select exclusivity provides access to Kindle Unlimited royalties averaging $0.0045 per page read (December 2024 data)
- ✓Net royalty calculations include delivery costs: $0.15 per MB for 70% royalty ebooks, deducted from gross earnings
Table of Contents
Amazon Ranking & Performance Terms
ACoS (Advertising Cost of Sales)
The percentage of your ad spend relative to attributed sales revenue. Calculated as (ad spend ÷ attributed sales) × 100. ACoS of 30% means you spent $30 in ads for every $100 in sales.
Why it matters: ACoS above 50% typically indicates unprofitable campaigns for most KDP books.
ASIN (Amazon Standard Identification Number)
Unique 10-character identifier assigned to every product on Amazon, including your KDP books. Format combines letters and numbers (e.g., B08XYZ1234).
Why it matters: Required for advertising campaigns, sales tracking, and customer service inquiries.
BSR (Best Sellers Rank)
Amazon's hourly-updated ranking system showing how your book performs against others in the same category. Lower numbers indicate better sales performance.
Why it matters: BSR under 50,000 typically indicates consistent daily sales, while BSR over 500,000 suggests minimal activity.
Category Rank
Your book's position within specific Amazon browse categories, separate from overall BSR. Books can rank in up to 10 categories simultaneously.
Why it matters: Category ranks under 10,000 often generate organic visibility and sales momentum.
CTR (Click-Through Rate)
Percentage of ad impressions that result in clicks, calculated as (clicks ÷ impressions) × 100. Industry average for book ads ranges 0.3-0.8%.
Why it matters: CTR below 0.2% indicates poor ad creative or targeting that needs optimization.
Impressions
Number of times your book or ad appears in Amazon search results or product pages, regardless of whether users click.
Why it matters: High impressions with low clicks suggest keyword targeting or cover design issues.
Organic Rank
Your book's natural search position without paid advertising influence, based on sales velocity, reviews, and relevance.
Why it matters: Organic ranks in top 20 search results drive 80% of discovery traffic according to Amazon data.
Expert Tip
Track BSR movement hourly during launches - drops of 100,000+ positions within 6 hours typically indicate algorithm penalties or competitor surge activity.
Royalty & Financial Terms
35% Royalty Rate
Lower royalty tier for ebooks priced under $2.99 or over $9.99, and for all sales outside KDP Select eligible territories.
Why it matters: Pricing at $2.98 vs $2.99 cuts your per-unit earnings nearly in half.
70% Royalty Rate
Higher royalty tier for ebooks priced $2.99-$9.99 sold in KDP Select eligible territories (US, UK, Germany, France, Spain, Italy, Netherlands, Japan, Brazil, Canada, Mexico, Australia, India).
Why it matters: This rate difference makes pricing strategy crucial for maximizing earnings per sale.
Delivery Costs
Amazon's charge for delivering ebook files to customers, deducted from 70% royalty earnings. Currently $0.15 per megabyte for most territories.
Why it matters: Large image files in children's books can reduce net royalties by $1-3 per sale.
KDP Select Global Fund
Monthly pool of money Amazon distributes to KDP Select authors based on Kindle Unlimited page reads. December 2024 rate: $0.0045 per page.
Why it matters: Page read earnings can exceed direct sale royalties for books with high engagement rates.
Net Royalty
Actual earnings after Amazon deducts delivery costs, taxes, and fees from gross royalty calculations.
Why it matters: Net royalty determines your real per-unit profit for business planning and pricing decisions.
Page Reads
Kindle Unlimited metric tracking how many pages subscribers read of your enrolled books, used to calculate KU earnings.
Why it matters: Books with higher completion rates earn more from KU than those with early drop-off patterns.
Print Royalty
Earnings from paperback sales, calculated as list price minus printing costs minus Amazon's cut (typically 40-60% of list price).
Why it matters: Print margins are much lower than ebook margins - often $1-3 per unit vs $2-7 for ebooks.
Expert Tip
Calculate break-even ACoS as your net royalty percentage - if you earn 40% net royalty, keep ACoS below 40% for profitability.
Publishing & Platform Terms
Author Central
Amazon's separate platform for managing author profiles, book pages, and accessing sales analytics beyond basic KDP reporting.
Why it matters: Provides more detailed sales data and customer demographic insights than KDP dashboard alone.
Browse Categories
Amazon's hierarchical system organizing books into specific topics and genres, with up to 10 categories allowed per book.
Why it matters: Category selection directly impacts discoverability and ranking competition levels.
KDP (Kindle Direct Publishing)
Amazon's self-publishing platform for ebooks and print-on-demand paperbacks, launched in 2007 as Digital Text Platform.
Why it matters: Primary revenue source for most indie publishers, controlling 60-70% of ebook market share.
KDP Select
Optional enrollment program requiring 90-day Amazon exclusivity in exchange for promotional tools and Kindle Unlimited access.
Why it matters: KU earnings can represent 30-60% of total revenue for enrolled fiction titles.
Kindle Create
Amazon's free formatting software for converting manuscripts into Kindle-ready files with professional layouts.
Why it matters: Eliminates need for expensive formatting services for standard text-based books.
Kindle Unlimited (KU)
Amazon's subscription service allowing unlimited reading of enrolled KDP Select books for $11.99/month.
Why it matters: KU subscribers represent 20-30% of Amazon's active readers according to industry estimates.
MOBI Format
Amazon's proprietary ebook file format, being phased out in favor of KPF (Kindle Package Format) as of 2024.
Why it matters: New uploads should use EPUB or DOC formats rather than legacy MOBI files.
Expert Tip
Use Author Central's geographic sales data to identify unexpected international markets worth targeting with localized keywords or translations.
Marketing & Advertising Terms
Amazon Ads
Pay-per-click advertising platform allowing KDP authors to promote books through Sponsored Products, Sponsored Brands, and Sponsored Display campaigns.
Why it matters: Primary discovery mechanism for new releases, with 70% of successful launches using paid advertising.
Attribution Window
Time period (typically 7-14 days) during which Amazon credits ad clicks with resulting sales for reporting purposes.
Why it matters: Sales may appear days after ad clicks, making daily campaign optimization misleading.
Bid
Maximum amount you're willing to pay per click in Amazon advertising auctions, set at keyword or targeting level.
Why it matters: Bid amounts directly impact ad visibility and cost per acquisition.
Campaign
Organizational structure within Amazon Ads containing related ad groups, keywords, and targeting parameters.
Why it matters: Campaign-level settings control budget, scheduling, and overall performance tracking.
CPC (Cost Per Click)
Actual amount paid when someone clicks your Amazon ad, typically 10-30% below your maximum bid due to auction dynamics.
Why it matters: Average CPC for book ads ranges $0.20-$0.80 depending on competition and genre.
Keywords
Search terms you target in Amazon advertising campaigns, matching customer queries to display your ads.
Why it matters: Keyword selection determines ad relevance and cost efficiency more than any other factor.
Negative Keywords
Terms you exclude from ad targeting to prevent irrelevant clicks and improve campaign efficiency.
Why it matters: Proper negative keyword lists can reduce wasted spend by 20-40% in mature campaigns.
Expert Tip
Set attribution windows to 14 days minimum for book ads - purchase decisions often take multiple research sessions over several days.
Content & Format Terms
Bleed
Extra image area extending beyond trim lines in print books, typically 0.125 inches, ensuring full-page designs print without white borders.
Why it matters: Missing bleed areas cause white edges and rejected print files during KDP upload.
DPI (Dots Per Inch)
Image resolution measurement for print quality, with 300 DPI required for KDP paperback interiors and covers.
Why it matters: Images below 300 DPI appear pixelated in print books and may cause file rejection.
EPUB
Industry-standard ebook format supported by most platforms, now preferred over MOBI for KDP uploads as of 2024.
Why it matters: EPUB files provide better formatting consistency across different Kindle devices and apps.
Gutter
Inner margin area where book pages bind together, requiring extra white space to prevent text from disappearing into binding.
Why it matters: Insufficient gutter margins make books difficult to read when opened, hurting customer satisfaction.
ISBN (International Standard Book Number)
Unique 13-digit identifier for published books, optional for KDP ebooks but required for wide distribution of paperbacks.
Why it matters: Amazon provides free ISBNs, but using your own allows broader distribution control.
Low-Content Books
Publications with minimal text like journals, planners, and coloring books, representing 30-40% of KDP catalog volume.
Why it matters: Different content guidelines and competition levels compared to traditional text-based books.
Trim Size
Final dimensions of printed book after cutting, with popular KDP sizes including 6"×9", 5.5"×8.5", and 8.5"×11".
Why it matters: Trim size affects printing costs, shelf appeal, and genre expectations for readers.
Expert Tip
Always design covers 0.125" larger than trim size on all edges - this bleed area prevents white borders if cutting is slightly off-center.
Terms Often Confused
KDP Select vs KDP
KDP is Amazon's publishing platform available to all authors. KDP Select is an optional enrollment requiring 90-day exclusivity for additional benefits like Kindle Unlimited access and promotional tools.
BSR vs Category Rank
BSR is overall ranking across Amazon's entire catalog in your primary category. Category Rank shows position within specific browse categories, with books potentially ranking in up to 10 different categories simultaneously.
Gross Royalty vs Net Royalty
Gross Royalty is the percentage rate (35% or 70%) before deductions. Net Royalty is actual earnings after Amazon subtracts delivery costs, taxes, and fees from the gross amount.
Impressions vs Page Views
Impressions count ad displays in search results and product pages. Page Views track visits to your book's detail page, whether from ads or organic traffic.
ASIN vs ISBN
ASIN is Amazon's internal product identifier used across their ecosystem. ISBN is the international standard for book identification used by libraries, bookstores, and distributors worldwide.
CPC vs ACoS
CPC is the cost per individual ad click. ACoS is the percentage of ad spend relative to attributed sales revenue, measuring overall campaign profitability rather than click costs.
Table of Contents
Frequently Asked Questions
What BSR number indicates good sales performance on Amazon KDP?▾
BSR under 50,000 in most categories typically indicates consistent daily sales, while BSR between 50,000-200,000 suggests occasional sales. BSR above 500,000 indicates minimal sales activity with weeks between purchases.
How much do KDP authors earn per page read in Kindle Unlimited?▾
KDP Select authors earned $0.0045 per page read from the Global Fund in December 2024. This rate fluctuates monthly based on total fund size and pages read across all enrolled books.
What's the difference between 35% and 70% royalty rates on KDP?▾
70% royalty applies to ebooks priced $2.99-$9.99 in select territories, while 35% applies to books priced outside this range or sold in non-qualifying countries. The rate difference can nearly double your per-unit earnings.
What ACoS percentage indicates profitable Amazon ads for KDP books?▾
ACoS should stay below your net royalty percentage for profitability. If you earn 40% net royalty, keep ACoS under 40% to maintain positive ROI on advertising spend.
Do I need an ISBN for my KDP book?▾
ISBNs are optional for KDP ebooks but required for paperback distribution beyond Amazon. Amazon provides free ISBNs, though using your own allows broader distribution control and publisher identification.
Related Resources
Genre Research
Category Research