If you’re an independent author, you can use these tools to help calculate your Cost-Per-Acquisition (CPA) for an ad and your estimated Revenue-Per-Sale (RPS) and Revenue-Per-Borrow (RPB).
As a general rule of thumb, a ‘winning’ ad is one that has a CPA that is less than your RPS if you are wide or less than your RPB if you are in KU.
You can find your KENPC number by going to your Bookshelf, hovering over the “…” and selecting KDP Select Info. The book’s KENP is listed at the bottom.
TOOLS
EZ Ad CPA Calculator
Cost Per Acquisition (CPA): $
Readthrough Calculator
To calculate RPS and RPB, export a KDP report from the Royalties Estimator page during a period of stable data.
Sales numbers should be pulled from the eBook sheet on the KDP report.
KENP Numbers should be pulled from the KENP Sheet.
Please ensure you are only inputting numbers from the region in which the book is being advertised, ex. United States.
You can also pull sales and read numbers from bookreport, readerlinks or bookedge as well.
Revenue Per Borrow: $
Revenue Per Sale: $