Amazon eBook File Optimization 2025: Reduce Delivery Fees, Boost Royalties

Author & Project Context

A US-based indie author approached Estorytellers with an 18-page illustrated short read. The book was targeted at children and young adults and included high-resolution color images on nearly every page. The initial Kindle file size was 18MB, which subjected the author to a significant delivery fee under Amazon’s 70% royalty model. At the original $4.99 list price, delivery fees were eroding nearly half of the potential per-unit royalty.

Challenges

• High file size leading to excessive delivery fees

• Risk of reducing the net contribution below profitability thresholds

• Maintaining visual quality for illustrated content without impacting reader experience

Strategy & Action Taken

1. File Compression & Optimization

   • Images were compressed using lossless methods to retain clarity.

   • Fonts and embedded elements were optimized to reduce redundant data.

   • PDF elements were reformatted to Kindle-native formats to lower file size.

2. Delivery Fee Analysis

   • Estorytellers calculated delivery fees at multiple candidate prices using the Kindle Royalty Cards artifact.

   • 18MB file size had a $2.70 delivery fee per unit, reducing the effective royalty drastically.

3. Decision & Implementation

   • File size was reduced from 18MB to 6MB.

   • Delivery fee dropped by approximately 66%, from $2.70 to $0.90 per unit.

   • The list price remained at $4.99 to maintain market positioning.

Results

• Net royalty per unit increased substantially without increasing the retail price.

• The book remained visually appealing to readers, preserving quality and engagement.

• Contribution per sale improved by over 60%, giving the author financial breathing room for advertising and promotions.

Quote
Pricing Analyst at Estorytellers: “Reducing delivery fees strategically can dramatically boost contribution without touching the retail price.”

Author Testimonial
“Estorytellers helped me see that my file size was silently cutting my earnings. Shrinking the images without losing quality transformed my royalties overnight.” — US Children’s Author