Interactive Co-Author Book Royalty & Revenue Split Calculator

Calculate your KDP or ACX co-author book royalty split instantly. Enter gross royalties, split percentages, and expenses to see each author's net payout. Free tool for 2026.

Mathematical Audit

Co-Author Book Royalty Split Formula

The calculation uses gross royalty income after platform fees, then deducts shared expenses before splitting by each author's agreed percentage.

KDP eBook Royalty (70%) = (0.70 × List Price) − Delivery Cost
KDP Paperback Royalty = (0.60 × List Price) − Printing Cost
Net Shared Pool = Gross Royalties − Shared Expenses
Author A Payout = Net Shared Pool × (Author A % / 100)
Author B Payout = Net Shared Pool × (Author B % / 100)

KDP pays 70% royalties for eBooks priced $2.99–$9.99. Paperbacks use a 60% royalty rate minus printing costs. All splits are applied after shared expenses are deducted from gross earnings.

Operational Guide

How to Use the Co-Author Book Royalty Calculator

1

Select book format and platform

Choose between KDP eBook (70% or 35%), KDP Paperback (60%), or ACX Audiobook (40% exclusive). The platform fee is applied automatically.

2

Enter monthly gross sales revenue

Input the total gross royalty payment you received from the platform before any splits or expenses.

3

Add shared expenses

Enter any costs shared between co-authors (cover design, editing, marketing) that should be deducted before splitting profits.

4

Set co-author split percentages

Enter each co-author's agreed percentage share. The tool validates that percentages total 100%.

5

View individual payouts

See each co-author's net payout after expenses, annual projections, and a visual breakdown chart.

Real-World Scenario Example

"Two authors co-wrote a $4.99 KDP eBook, selling 300 copies/month with $200 in shared expenses and a 60/40 split."

Inputs

grossRoyalties:1047
sharedExpenses:200
authorASplit:60
authorBSplit:40
format:ebook-70

Result

Net pool = $847. Author A receives $508.20 (60%), Author B receives $338.80 (40%) per month.

Important Disclaimer

These estimates are for educational purposes. Actual royalties depend on KDP pricing tiers, delivery costs, territory eligibility, and ACX distribution type. Always verify your actual payouts in your KDP or ACX dashboard.