# Calibre **URL:** [https://calibre-ebook.com/about](https://calibre-ebook.com/about) ↬ [Calibre User Manual](https://manual.calibre-ebook.com/index.html) --- Searching can be fine-tuned, e.g. ``` author:Asimov and not series:Foundation title:"The Ring" or "This book is about a ring" format:epub publisher:feedbooks.com ``` `tag:"=science"` will match science, but not science fiction or hard science. Character variants are significant: é doesn’t match e.