Four hours, for the course you almost certainly mean. Florida's Basic Driver Improvement, the one you elect within 30 days of a citation, is a 4-hour course by state rule, the same at every FLHSMV-approved school, making it one of the shortest ticket courses in the country.
The confusion to avoid is buying the wrong Florida course entirely. Florida also runs Advanced Driver Improvement at 8 and 12 hours, which serves court orders and habitual-offender license reinstatement, a different tool for a different problem. A driver electing on an ordinary ticket wants the 4-hour BDI, and a course page pushing you toward a longer Florida course for a standard election deserves suspicion.
One clock clarification that relieves people: the famous 30-day deadline is for electing the course with the clerk, not completing it. Elect in time and the completion window runs on the clerk's schedule, with the course itself savable across sittings. Four hours against that window is the easy part; the election deadline is the part that bites.
Every approved online BDI course we track is compared on the Florida page, and the once-per-12-months, eight-per-lifetime rationing (s. 318.14(9), as amended 2025) is on our frequency page.