# What is EPUB 2?

Source: https://epublab.com/glossary/epub-2/ (updated 2026-11-03)

EPUB 2 is the previous generation of the EPUB standard (2.0.1 dates from 2010), based on XHTML 1.1 and an NCX table of contents. It has been superseded by EPUB 3 but many older files still use it.

## Why it matters when you convert a PDF to EPUB

There is no reason to produce EPUB 2 from a PDF today: current readers, Send to Kindle and Kobo all accept EPUB 3. EPUB 2 matters when you validate or repair older files, because EPUBCheck validates them against the EPUB 2 rules and reports messages that only apply there, such as NCX identifiers.