The East India House, and before 1767 became one of the auditors of Indian accounts. His leisure hours he devoted to the study of Latin and especially Italian, and began writing translations of the chief works of the Italian poets. He published translations of the Jerusalem Delivered of Tasso in 1763, the Orlando Furioso of Ariosto in 1773-1783, the Dramas of Metastasio in 1767, and Rinaldo, an early work of Tasso, in 1792. Among his plays are: Cyrus (1768), Timanthes (1770) and Cleonice, Princess of Bithynia (1775), none of which achieved success. The verses of Hoole were praised by Johnson, with whom he was on terms of intimacy, but, though correct, smooth and flowing, they cannot be commended for any other merit. His translation of the Orlando Furioso was superseded by the version (1823-1831) of W. S. Rose. Hoole was also the friend of the Quaker poet John Scott of Amwell (1730-1783), whose life he wrote; it was prefixed to Scott's Critical Essays (1785). In 1773 he was promoted to be chief auditor of Indian accounts, an office which he resigned in 1785. In 1786 he retired to the parsonage of Abinger, Surrey; and afterwards lived at Tenterden, Kent, dying at Dorking on the 2nd of April 1803.
See Anecdotes of the Life of the late Mr John Hoole, by his surviving brother, Samuel Hoole (London, 1803). Some of his plays are reprinted in J. Bell's British Theatre (1797).