How many keywords does Amazon KDP allow?

What to put in the seven slots
SlotAngle
1-2Main reader problem or topic
3-4Audience and reading level
5Format or occasion (gift, workbook, large print)
6-7Long-tail variants and synonyms

Do KDP keywords influence categories?

They can. Amazon uses keywords to place books in some browse categories, alongside the BISAC categories chosen at publication, which is why phrasing the slots around real reader searches matters.

Can keyword slots be changed after publishing?

Yes. Keywords can be edited in the KDP bookshelf at any time, and the change is re-indexed within a few days.