Validate your EPUB, now

Drag & drop an EPUB and get a clear pass / warn / fail report. You should do this before you send your books to retailers or distributors!

Upload Your EPUB

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  1. UploadYour EPUB goes straight to temporary storage, without being shared with anyone.
  2. ValidateW3C's EPUBCheck tool inspects structure, metadata, and content in the background.
  3. ReviewGet a pass/fail and itemized report of every error, warning, and hint.