Eugene Thill, formerly an inmate in the Department of Corrections, seeks review of a final order dismissing his petition for a writ of mandamus in which he challenged the Department’s calculation of gain time credits. Because official records indicate, and the State has confirmed, that Mr. Thill was released from prison during the pen-dency of this appeal, we dismiss the appeal as moot. See Doty v. Fla. Dep’t of Corrections, 964 So.2d 258, 258-59 (Fla. 1st DCA 2007); Moore v. Moore, 764 So.2d 676, 677 (Fla. 1st DCA 2000) (“A petition that goes to the length of confinement, rather than *954to the fact of confinement, is mooted by the inmate’s release.”).
DISMISSED.
KAHN, WEBSTER, and VAN NORTWICK, JJ., concur.