J.K. Rowling’s first name is Joanne.
She was born Joanne Rowling on 31 July 1965 in Yate, Gloucestershire, England. The initials “J.K.” became her publishing name when Bloomsbury asked for a name that might appeal broadly to young readers.
Rowling did not originally have a middle name. For the Harry Potter books, she adopted the additional initial “K,” standing for Kathleen, her paternal grandmother’s name. This created the pen name J.K. Rowling.
The name is sometimes mistakenly expanded as “Joanne Kathleen Rowling,” but “Kathleen” was added as part of her author name rather than being her birth middle name. Rowling has also published crime novels under the pseudonym Robert Galbraith.