Roulette, blackjack and table games
How can I work out the probability of one specific number in European roulette?
Direct answer
One specified number on a fair single-zero European wheel has probability 1/37 = 2.7027% per spin.
How to use this answer
This answer is based on the mathematical principle or published rule identified in the source below. If the question involves a live betting market, confirm its settlement definition before applying it to a specific bet.
One number has probability 1/37, approximately 2.70%, on a fair single-zero wheel.
Separate the game’s mathematical probabilities from the casino’s house procedure. The odds may be calculable even where split, surrender, side-bet or payout policies differ between tables.