Whenever possible, we recommend keeping your ebook free for more than a single day.
Readers do not all discover or click books at the same time. A longer free period gives readers additional opportunities to find your book while the free price is still available.
This can be particularly helpful with The Fussy Librarian because reader recommendations are personalized, and a book may continue reaching interested readers after its originally scheduled promotion date. We strongly recommend promoting with us on Day 1 of your giveaway.
If you are using Amazon KDP Select free days, your available promotional window may be limited. In that case, use the longest window that makes sense for your overall strategy.