2 Chronicles 26:1, 3-4

And all the people of Judah took Uzziah, who was sixteen years old, and made him king instead of his father Amaziah.

Uzziah was sixteen years old when he began to reign, and he reigned fifty-two years in Jerusalem. His mother’s name was Jecoliah of Jerusalem. And he did what was right in the eyes of the LORD, according to all that his father Amaziah had done.