RoyaltyPeek turns a book's Best Sellers Rank into an estimated sales and royalty range — shown on the Amazon page you're already on. No calculator site, no copy-pasting ranks between tabs.
The free calculators are all websites. RoyaltyPeek lives where you actually research — on the book page.
Everything you need to size up a title's earning potential, the moment you open it.
Open any book and the estimate is already there — no switching to a BSR calculator, no pasting a rank into a website.
Estimates show as ranges with a clear basis label, so you never mistake a guess for a guarantee.
Set your real Kindle royalty % and print payout in Settings so the estimate matches your actual margins.
Reads only the page you have open. No Amazon API, no search-result scraping, no tracking, no analytics.
Three seconds, zero tabs.
Any Kindle, paperback or hardcover product page.
RoyaltyPeek reads the BSR and price and shows estimated sales and royalties per day, week and month.
Judge a niche or a comp title at a glance — no calculator, no spreadsheet.
A quick primer — the same logic RoyaltyPeek runs automatically on the page.
Best Sellers Rank (BSR) reflects a book's recent sales compared to others in its store. A lower BSR means more recent sales. There's no official BSR-to-sales formula, so estimators map rank to a sales-per-day curve built from real author data — roughly, a Kindle book around #2,000 sells dozens a day, while #100,000 sells around one a day.
Royalties depend on format. On Amazon.com, Kindle earns about 70% of list price for books priced $2.99–$9.99 (35% outside that band), while paperback and hardcover earn a royalty rate minus printing cost, which scales with page count. RoyaltyPeek applies the right rule per format and shows the result as a range.
The catch with calculator websites is the workflow: find the rank, copy it, switch tabs, read a number, switch back — for every title. RoyaltyPeek removes that entirely by estimating on the page itself.
BSR is the number Amazon assigns to a book based on recent sales relative to other titles. A lower number means more recent sales. RoyaltyPeek reads the BSR on the page and converts it into an estimated sales and royalty range.
They're rough estimates shown as ranges, not exact figures. BSR is volatile and varies by format, marketplace and Kindle Unlimited borrows. The curves are calibrated to widely used industry data, but actual sales will differ.
Yes. RoyaltyPeek detects the format you're viewing and applies the matching sales curve and royalty rule — 70%/35% for Kindle by price, and a printing-cost-aware royalty for paperback and hardcover.
Because you have to leave the book, find the rank, copy it into another tab, read a number, and come back — for every book. RoyaltyPeek shows the estimate on the Amazon page you're already on. No calculator, no copy-paste.
Yes. RoyaltyPeek reads only the page you have open, in your browser. It doesn't use the Amazon API, doesn't scrape search results, and sends no browsing data anywhere.
A one-time payment of $3.99 unlocks RoyaltyPeek for life. No subscription.