My economics of selling books:

$20 book on @Gumroad - I net $19 (Gumroad takes 3.5% + $.30)

$22.50 print book on Amazon - I net $9.50 (Amazon takes 40% of the sale price + $4/book KDP print)

$22.50 Kindle on Amazon - I net $7.70 (Amazon takes 65% of the sale price)

(cont'd)

$22.50 book bought in a US bookstore, fulfilled by Ingram Spark - I net around $5.86 (55% wholesale discount)

$22.50 book bought through iBooks - I net $9 (listed it through Ingram Spark)

I did not go through book publishers, but here's how amounts would look, from contracts:

A $22.50 book through:

A "classic" publisher: $1.50-2/book (with a "classic" publisher like O'Reilly, Manning or similar: 10-12.5% royalty from the net price)

Smaller publishers (e.g. Packt): $2-4/book (up to 20% of net)

The Pragmatic Bookshelf: up to $11 (50% in royalties)

So why would *anyone* go with a publisher?

Distribution and help.

The only way I get sales on Gumroad is by me directing people there. Amazon takes a large cut: but also serves as a discovery platform. Publishers bring reach & also a lot of resources to create a quality book.

Self-publishing means you need to take care of:
- Writing
- Editing
- Production work (cover etc)
- Figuring out how everything works
- Accounting, expenses
- Marketing & book promotion
- Returns
- Invest money upfront vs getting paid by the publisher on completion of the script