Bookfolio Fixer

Bookfolio Fixer checks an EPUB against the official specification and repairs problems that are safe to fix automatically, such as mimetype packaging, missing manifest entries, a missing navigation document and duplicate IDs. Issues that need a human decision are reported for review instead of being changed. It shows a before and after summary and offers the repaired EPUB for download. The first 3 fixes need no account, and a free account gives 10 a month.