Flush draw odds: turn, river and both
Outs
With 9 outs, a flush draw hits on the turn 19.1% of the time and by the river 35.0% of the time when you see both cards.
- 19.6%hit on the river, from the turn
- 1.9 to 1odds against, both cards to come
- 4.2 to 1odds against, next card only
- 36%the rule of 4 estimate
- 25%equity needed to call a half-pot bet
The Core Probabilities
A flush draw typically holds nine outs. The table shows the chance to hit on the next card is just under one in five. If you see both remaining community cards, the combined chance rises to roughly one in three. This difference matters because betting rounds change how many cards remain unseen. You must know which figure applies to your current situation. The odds against hitting with both cards to come are less than two to one. With only one card left, the odds against stretch to more than four to one. These figures assume a standard deck and no dead cards affecting your outs. Use the calculator to verify specific scenarios where dead cards might alter the count slightly. For further support, see help and support.
| Cards to come | Chance to hit | Odds against |
|---|---|---|
| Turn, one card | 19.1% | 4.2 to 1 |
| River, one card | 19.6% | 4.1 to 1 |
| Turn or river, both cards | 35.0% | 1.9 to 1 |
When to Use Which Figure
Use the single-card probability whenever another round of betting will follow. If an opponent bets the turn, you must decide based on the next card alone. The chance to hit improves slightly on the river because fewer cards remain in the deck. However, you still face a significant hurdle. Use the combined probability only when betting stops, such as in an all-in situation or when checking down the hand. In these cases, you see both cards without further decisions. The rule of four offers a quick estimate for the combined chance. It approximates the exact figure closely enough for fast decisions. For precise calculations, rely on the exact percentages rather than the shortcut.
Comparing Odds to Bet Sizes
Compare your chance to hit against the cost to continue. A half-pot bet requires you to win often enough to justify the call. The required equity for such a bet is lower than your combined chance to hit. This means calling is mathematically sound when you see both cards. If betting continues, only the next card counts, and its chance to hit is below the equity a half-pot call needs. The single-card chance is often insufficient to call a large bet immediately. Implied odds can bridge this gap if you expect to win more money later. See implied odds for details on future winnings. Always weigh the immediate cost against the specific probability available to you.
Practical Application
Understanding these distinctions prevents overcalling or undercalling. Many players misapply the combined probability to single-card decisions. This error leads to calling bets that are too large for the immediate chance. Conversely, ignoring the combined chance in all-in spots causes unnecessary folds. The rule of two works well for single cards, while the rule of four suits combined scenarios. These shortcuts align closely with the exact figures provided. For deeper analysis, consult the outs and pot odds guide. It explains how dead cards influence your effective outs. Precise calculation ensures you do not rely on guesswork during critical moments.
Questions
Why is the chance higher when seeing both cards?
Seeing two cards gives you two opportunities to hit your outs instead of one. The combined probability accounts for hitting on either the turn or the river, increasing the overall likelihood of completing your draw.
Does the rule of four replace exact calculations?
It provides a quick estimate close to the exact figure. Use it for fast decisions, but rely on precise percentages when the situation is tight or when dead cards significantly affect your outs.
How do dead cards affect these odds?
Dead cards reduce your effective outs, lowering the probability slightly. The standard figures assume a full deck. Adjust your calculation if you know specific cards are already out of play.
Are implied odds necessary for flush draws?
Not always. If the immediate pot odds justify the call, implied odds are secondary. They become crucial when the immediate chance is borderline, helping justify calls with larger future winnings.
Every figure on this page is computed by code from a standard 52-card deck, counting every possible card and checking the count a second way. See the methodology.