Do Publishers Use Mobi Services For Digital Book Releases?

As someone who follows the digital publishing scene closely, I've noticed that mobi files were once a go-to format, especially for Kindle users. Amazon's Kindle Direct Publishing heavily relied on mobi for years, making it a staple for indie authors and big publishers alike. However, since 2022, Amazon shifted focus to EPUB formats, phasing out mobi support. Many publishers still have back catalogs in mobi, but new releases are increasingly EPUB-only. It's a transition period, and while you might stumble upon older titles in mobi, the industry is clearly moving toward EPUB for its versatility and broader compatibility across devices.

Smaller publishers or self-published authors might still offer mobi out of habit or to cater to readers with older Kindle models. But for most mainstream releases, EPUB is now the default. The shift reflects the broader trend in digital publishing—standardizing formats to simplify distribution and improve accessibility.

I've worked in digital publishing for years, and the mobi format has been a topic of debate. Early on, it was indispensable because Amazon’s ecosystem dominated the e-reader market. Publishers had no choice but to prioritize mobi for Kindle compatibility. But times have changed. With Amazon’s 2022 announcement deprecating mobi in favor of EPUB, the landscape shifted overnight. Most major publishers now skip mobi entirely, focusing on EPUB and sometimes PDF for niche audiences.

The transition hasn’t been seamless, though. Some readers still swear by mobi, especially those with older Kindles. I’ve seen smaller presses and self-published authors hedge their bets by offering both formats, but it’s extra work for diminishing returns. The irony? EPUB was always the better format—more flexible, better typography, and widely supported outside Amazon’s walled garden. The industry’s shift feels like catching up to reality.

From a tech perspective, mobi’s limitations (like no reflowable text in older versions) made it a relic. Publishers today want formats that work across platforms, from Kobo to Apple Books. EPUB 3’s interactive features are a bonus for children’s books or educational content. The only holdouts are readers clinging to ancient Kindle models, and even Amazon’s pushing them to upgrade. So, while mobi isn’t entirely dead, its role in new releases is fading fast.

As a book blogger who tests e-reader formats regularly, I can confirm mobi’s decline. Amazon’s decision to drop mobi support for new submissions was a wake-up call. These days, when I download advance review copies from publishers, they’re almost exclusively EPUB. The few mobi files I encounter are usually legacy titles or from authors who haven’t updated their workflows.

What’s interesting is how readers react. On forums, I see debates between EPUB purists and mobi loyalists—the latter often cite mobi’s stability on older Kindles. But let’s be real: EPUB looks better. The formatting is cleaner, and it supports fonts and layouts that mobi butchered. For graphic-heavy books like manga or cookbooks, EPUB is a game-changer.

Publishers aren’t sentimental about formats; they follow reader demand and tech trends. With EPUB now the universal standard outside Amazon, mobi feels like a nostalgia trip. Even Kindle users can sideload EPUB these days. The only reason to use mobi now is if you’re stuck with a 10-year-old Kindle—and at that point, maybe it’s time for a new gadget.