Gambling terms, explained straight

Odds, Probability & Bankroll

Probability of flush in 5-card poker

In 5-card poker, a flush is five cards of the same suit. The probability measures how often a random hand will meet that condition, ignoring straight flushes and royal flushes.

Number of flush hands
5,108 (excluding straight and royal flushes)1
Total 5-card hands
2,598,9601
Probability
0.0019654 (0.19654%), or about 1 in 508.83

Key points

  • A flush requires all five cards in the same suit, but a straight flush or royal flush does not count as a flush here.1
  • The probability is fixed for any standard 52-card deck and does not vary by game variant or payout table.3
  • Some sources round this to 0.20%.2

Where this term is used

Not the same as

Sources

  1. Poker probability en.wikipedia.org Provides the count of flush hands (5,108) and total hands (2,598,960).
  2. Five-card draw en.wikipedia.org Supports the rounded probability of 0.20%.
  3. Poker Probabilities wizardofodds.com Gives the exact probability 0.0019654 and the 1 in 508.8 figure.

Sources are drawn from regulators, universities and published research, and each one is labelled with what it actually is — a preprint is not called a paper. Bookmaker and affiliate pages are never cited here, because a page that sells betting is not a neutral authority on it.