Indie authors talk about KDP Select and going wide as though they are tribes. They are not. Enrolment in Select is a 90-day contract on a single ebook, it auto-renews unless you switch that off, and you can hold different titles under different terms at the same time. So the question worth answering is narrower than "should I go wide": it is whether this particular book, in this particular genre, at this point in your catalogue, earns more inside Amazon's subscription pool than outside it.
What exclusivity actually covers
KDP Select locks the digital edition of that title to Amazon for the enrolment period. Your paperback, hardback, audiobook and any translations into other languages are unaffected, and you can sell those anywhere you like. You may post up to 10% of the book as a sample on your own site.
The part that catches people out is that your own website counts as another retailer. While a book sits in Select, you cannot sell that ebook direct from your own shop, put it on Kobo, or hand it out as a permanent reader magnet. Listing it elsewhere before the enrolment period ends can get the title pulled and your account reviewed, and turning off auto-renew does not end the current 90 days early.
What Amazon gives you for it
Page reads are the main prize. Kindle Unlimited borrows pay from a global fund that Amazon publishes each month and that has run in the tens of millions of dollars, divided across all pages read. The effective rate has hovered around half a cent per KENP page for years, so a full read of a book normalised to 300 pages lands somewhere near $1.35. That is less than a $2.99 sale, but a borrow costs the reader nothing extra, which is why browse-heavy genres pick up volume from it.
You also get Kindle Countdown Deals and five free promotion days per enrolment period, plus the 70% royalty rate in a handful of markets, including Japan, Brazil, India and Mexico, where non-Select titles are capped at 35%.
What wide gives you instead
Outside Select you can list on Apple Books, Kobo, Google Play, Barnes & Noble and library systems such as OverDrive, either direct or through an aggregator like Draft2Digital, which takes roughly 10% of list price for doing the uploads and paying you from one dashboard.
Pricing behaves differently off Amazon. KDP pays 70% only between $2.99 and $9.99, and deducts a delivery charge based on your file size, which is why image-heavy books lose more than plain novels. Apple Books pays 70% at any price, so a 99p series starter or a $19.99 non-fiction title returns considerably more per copy there. You can also run a permanently free book one, which Amazon will only match rather than let you set.
And you can sell the ebook yourself, at full margin, to a list you own.
Run it on your own numbers
Your KDP dashboard already tells you what the decision costs. Work out what share of your Amazon income came from page reads over the last six months. That figure is what going wide has to replace, and other retailers rarely replace it in the first quarter. Wide income tends to build slowly because discovery on Kobo and Apple leans on merchandising, series depth and repeat readers rather than a single algorithm.
Some rough guidance that holds more often than not: if page reads are over half your income and you write in a genre where subscribers binge series, exclusivity is doing real work. If page reads are a small slice, if you write non-fiction that readers find through search or your own audience, or if you are writing one book rather than eight, the lock-in is buying you less than it costs.
A split catalogue is legitimate. Keep the series that feeds on page reads in Select, take the standalones and the back catalogue wide, and give the wide titles twelve months before you judge them.
Whichever way you go, own the middle
Every route above ends at a retailer's customer, not yours. The exception is the direct channel: your own site, your own mailing list, your own checkout. •BulletPoint Publishing's Indie Author Toolchest gives indie authors an author website, mailing list, direct ebook sales, ARC distribution and a press kit for one flat monthly fee, so when you do come out of Select the shop is already built.
Because a split catalogue is normal, the settings are per book and you can flip them at any time. Each title has its own channel choice, set separately for the ebook and the physical edition: either "I sell it myself" through the platform's checkout, or "Sold via Amazon", which shows a geo-routed buy link and takes no payment. There is also a KDP Select checkbox per book, and ticking it puts a warning in front of you before you generate in-person redemption codes for that title, since handing out copies of an enrolled ebook may breach the exclusivity clause. It warns rather than blocks, so the call stays yours. When a 90-day term ends and you want that book direct, you change the setting and the buy button changes with it. Have a look at what's in the Toolchest.