J.K. Rowling’s first name, as in her birth name Joanne Rowling, is Joanne.
She was born Joanne Rowling on 31 July 1965 in Yate, Gloucestershire, England. The initials in her pen name do not represent a middle name originally given at birth. Her publisher suggested using initials for the Harry Potter books, partly because a gender-neutral author name was considered appealing to young male readers.
Rowling later adopted the initial K from Kathleen, her paternal grandmother’s name, for publication. She is therefore widely known as J.K. Rowling, although “Joanne Rowling” remains her legal and biographical name in many references. A common mix-up is assuming that the K was part of her original full name; it was selected for her publishing identity rather than recorded as her birth middle initial.