What does the black-and-white flag mean in F1?

The black-and-white flag, split diagonally, is a warning for unsporting behaviour such as repeatedly running off track to gain an advantage or dangerous defending. Shown with the driver's number, it is a caution that a penalty may follow if the behaviour continues, much like a yellow card in football. A separate black flag with an orange circle is used instead to tell a driver their car has a mechanical problem and must pit. Neither is a disqualification on its own.

See also: F1 flags explained.

Related race procedure & flags terms

• Formation lap — The single lap the field completes behind no one to reach the grid, warming tyres and brakes before the start.
• Parc fermé — The "closed park" rules that lock a car's set-up from the start of qualifying, banning most changes before the race.
• Safety Car — A road car sent onto the track to lead and slow the field when there is a hazard, bunching the pack.
• Virtual Safety Car (VSC) — An electronic slow-down that holds every car to a set delta time without deploying the physical Safety Car.
• Yellow flag — Warns of a hazard ahead: slow down, no overtaking. Double waved yellows mean a serious hazard and be ready to stop.
• Red flag — Stops the session immediately; cars return to the pits or grid because conditions are unsafe to continue.
• Blue flag — Shown to a driver about to be lapped, telling them to let the faster leading car through.
• Black flag — Shown with a driver's number, it orders that driver to return to the pits — they are disqualified or excluded.
• Chequered flag — The black-and-white checked flag waved at the finish line to signal the end of the session or race.

Definition written in plain language from the current F1 sporting rules and common usage, current as of 14 August 2026. Unofficial; not affiliated with Formula 1.