# What is a soft hyphen?

Source: https://epublab.com/glossary/soft-hyphen/ (updated 2026-11-03)

A soft hyphen (U+00AD) is an invisible character that marks where a word may be split; it only shows as a hyphen when the line actually breaks there. In a PDF, a hyphen at the end of a line can be a soft hyphen or a real one.

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

A converter must rejoin words that were split at the end of a PDF line ("conver- sion" becomes "conversion") without merging real hyphenated compounds. EPUBLab rejoins a word when the PDF marks the hyphen as a line break, or when the next line starts in lowercase, and lets the e-reader hyphenate the EPUB again for its own line length.