What do the initials “J.K.” represent in J.K. Rowling’s name?

The initials “J.K.” in J.K. Rowling’s name represent Joanne Kathleen.

Rowling was born Joanne Rowling and did not originally have a middle name. Her publisher requested a two-initial pen name for the Harry Potter books, partly because a gender-neutral presentation was thought likely to appeal to boys. Rowling chose Kathleen as an additional initial in honor of her paternal grandmother, Kathleen Ada Bulgen.

The name “J.K. Rowling” therefore combines her first name with a later-added middle initial and her surname. She has sometimes been referred to simply as Jo, a name she has used personally and professionally in interviews and charitable work.

The initials are not an abbreviation for “Joanne Katherine,” and the K does not come from Rowling’s birth certificate. In the United States, her first Harry Potter book was published under the name J.K. Rowling even though the title changed from Philosopher’s Stone to Sorcerer’s Stone.