May 29, 2024

Google Is Now Indexing EPUB Files

Google Is Now Indexing EPUB Files


Google has quietly updated its documentation to announce that it is now indexing EPUB files, a popular format for eBooks used by e-readers. This new capability allows EPUB documents to appear in search results, enhancing the discoverability of eBooks and other EPUB-formatted content.

What is EPUB?

EPUB is an XML-based eBook publishing format developed by the International Digital Publishing Forum (IDPF). In 2016, the IDPF merged with the World Wide Web Consortium (W3C) to integrate electronic book publishing with the Internet, aiming to enrich both fields through mutual collaboration.

Google’s Indexing of EPUB Content

Google’s decision to index EPUB content aligns with the goal of merging e-publishing with the Internet. Although it took eight years for this update, it signifies a significant step in how digital books and documents are accessed via search engines. Google’s changelog succinctly noted the addition of EPUB to its list of indexable file types, with the following statement:

Google Is Now Indexing EPUB Files

Does Google Rank EPUB Content?

To test if Google ranks EPUB content, a search was conducted for a specific scientific research document titled “Consumption of Contaminated Lake Fish and Reproduction” hosted on journals.lww.com. The search results did not directly show the EPUB document but did display the webpage containing the EPUB download link.

Google’s documentation indicates that while EPUB files are indexable, they are not necessarily ranked in search results like standard web pages. Users can still locate EPUB documents using the filetype:epub search operator, but these documents may not appear prominently in regular search results.


Google’s addition of EPUB to its indexable file types marks an important development for the accessibility of eBooks and other digital publications. Although EPUB documents may not yet rank highly in standard search results, their inclusion in Google’s index ensures they are searchable and accessible through specific queries. This update broadens the scope of content discoverable via Google, benefiting both users and publishers in the digital book space.