Purifoy revealed his decision after Florida lost its final game of the season, 37-7 to No. 2 Florida State, in which he made his second interception of the season.
The 6-foot, 185-pound Purifoy, is the No. 5 defensive back eligible for the draft, according to ESPNs Todd McShay. Purifoy finished the season with 24 tackles, two interceptions, seven pass breakups and sack sacks.
Purifoy, a junior who also saw time on offense, ran an interception back for a touchdown Oct. 5 against Arkansas.
He was one of five Gators suspended for the season opener for a violation of team rules.
Florida finished the season 4-8 and will not play in a bowl game.