Should I use KDP or Books.by?

Use KDP for Amazon discovery and Books.by for direct-to-reader sales. KDP is a marketplace; Books.by is your owned storefront with customer data and direct-sale economics.

Does Books.by replace Amazon KDP?

Not usually. Most authors should keep KDP for readers who shop on Amazon and add Books.by for traffic they generate themselves.

Which pays more per direct sale?

Books.by usually pays more on direct sales because it charges no platform commission while print, shipping, and card costs still apply. KDP royalties are based on Amazon's royalty rate minus print cost.

Marketplace vs owned store

KDP vs Books.by: Use Amazon for Discovery, Books.by for Readers You Already Earned

KDP is excellent at one thing: selling books inside Amazon. Books.by is built for the other part of the author business: your storefront, your customer relationship, and the economics of direct demand.

60%KDP paperback royalty rate before print cost

0%Books.by platform commission; print, shipping, and card costs still apply

FastStripe-powered payout cadence

FullCustomer data with Books.by

Verdict

KDP is where Amazon shoppers buy. Books.by is where your audience should buy.

The mistake is sending newsletter, event, and social traffic to Amazon by default. That traffic is already yours. A direct storefront lets you keep more margin and learn who bought.

Run the royalty trade-off

Same paperback, same price, different channel economics.

Retail price

Page count

Interior

Direct copies/year

Books.by royalty$0.00Retail minus estimated print cost; no Books.by platform commission. Shipping and card costs still apply.

KDP royalty$0.0060% list price minus print cost.

Break-even on $99/year0 copiesApproximate copies needed before direct lift covers the flat fee.

Decision point	KDP	Books.by
Core job	Amazon marketplace sales	Direct-to-reader storefront sales
Customer data	Marketplace owns the relationship	Author sees customer/order data
Payout timing	Typically delayed royalty cycle	Stripe-powered payout cadence
ISBN path	ASIN for Kindle; optional KDP print ISBN	ISBN support for eligible Books.by print books
Best traffic	Amazon search and Amazon loyalists	Email, events, ads, social, podcast, website

When KDP wins

Discovery and reader habit

If someone starts on Amazon or strongly prefers Amazon checkout, KDP is the natural path. Do not fight that behavior.

When Books.by wins

Owned demand

If the reader came from your work, your list, your talk, or your campaign, direct checkout protects the relationship and the margin.

Best stack

Use both deliberately

Keep KDP available. Make Books.by the primary link in your owned channels, launch pages, QR codes, and author website.