Google Quietly Adds EPUB Files to Search Index

Google announced that it is now indexing .epub documents, a format commonly used to print books for e-readers. Google is already showing EPUB books in the search index.

EPUB File Format

EPUB is a format for publishing eBooks that is based on XML. It was created by the International Digital Publishing Forum and later merged with the World Wide Web Consortium in 2016. The aim of this merger was to connect eBook publishing with the Internet in order to enhance both platforms.

Google Indexing EBUB Content

The reason for combining e-publishing with the Internet is in line with Google's choice to include EPUB content in its indexing system. It may come as a surprise that it took eight years for this to happen. The update simply states that EPUB files are now part of Google's list of indexable file types, without providing any additional information.

Google's official update straightforwardly mentions the addition of EPUB file format to its indexable file types list.

“Adding epub to indexable file types

What: Added EPUB to the list of indexable file types.

Why: Google Search now supports epub.”

Does Google Rank EPUB Content?

I first searched for EPUB content using the site:search function. I found a scientific research paper titled "Consumption of Contaminated Lake Fish and Reproduction" on the journals.lww.com domain.

Next, I tried searching for the same document using the exact keyword phrase and a variation of it ("Consumption of Contaminated Fish in Lake Ontario") in the regular search. Google didn't show the EPUB document itself, but it did show the webpage where the document could be downloaded.

Screenshot Of EPUB Download Page

Google's official documentation on indexable file types simply states that the filetypes listed are indeed indexable. As of now, it is safe to assume that Google does not rank EPUB documents, but they will show up in search results when using the filetype:epub search.

File types indexable by Google

Featured Image by Shutterstock/Simple Line

Editor's P/S:

The inclusion of EPUB files in Google's indexing system is a significant step towards enhancing the accessibility of digital books. By making these documents searchable and discoverable through regular search queries, Google is bridging the gap between traditional publishing and the vast online audience.

While the current lack of ranking for EPUB content may be a limitation, it is likely a temporary measure. As Google continues to refine its search algorithms and explore the potential of this format, it is reasonable to expect that EPUB documents will eventually gain prominence in search results. This would further empower authors, publishers, and readers alike by expanding the reach and impact of digital books.