Poker Odds Calculator — Outs & Draw Probability
Enter your outs and the current street (flop or turn) to see the exact probability of completing your draw, plus the quick rule-of-2/4 approximation and the odds-against ratio.
Street (position in hand)
Exact probability of completing your draw by the river
- 1
P(miss on turn)
(38 ÷ 47) = 0.808538 non-out cards out of 47 unseen. - 2
P(miss on river | missed turn)
(37 ÷ 46) = 0.8043 - 3
P(miss both cards)
0.8085 × 0.8043 = 0.6503 - 4
Probability of hitting (%)
(1 − 0.6503) × 100 = 34.97
How does this calculator work?
Count your outs (cards that complete your hand), then multiply by 4 on the flop or 2 on the turn for a quick percentage. The exact formula is 1 − [(unseen−outs)/unseen × (unseen−1−outs)/(unseen−1)] on the flop, or outs/46 on the turn. Use this to compare with pot odds.
Formula
How this is calculated
In Texas Hold'em, 'outs' are the cards remaining in the deck that will complete your drawing hand. Starting from 52 cards, subtract your 2 hole cards and the 3 board cards on the flop (leaving 47 unseen), or 4 board cards on the turn (leaving 46 unseen). The probability of hitting at least one out across the remaining streets is computed as 1 minus the probability of missing all streets.
The rule of 2 and 4 is a practical mental shortcut: multiply outs × 4 on the flop for the two-card probability, or outs × 2 on the turn for the one-card probability. This approximation is accurate within 1–2 percentage points for 4–15 outs and is widely used at the table for quick decisions.
Common draws by outs: flush draw = 9 outs (≈ 35% from flop); open-ended straight draw = 8 outs (≈ 31%); gutshot straight = 4 outs (≈ 17%); two overcards = 6 outs (≈ 24%). These figures assume your outs are all clean — in practice, some outs may improve your opponent's hand too and should be discounted.
Frequently asked questions
Identify which ranks/suits complete your best hand. A flush draw has 13 cards of one suit minus the 2 in your hand and the 2 on the board = 9 outs. An open-ended straight draw has 4 cards at each end = 8 outs. Subtract any 'tainted' outs that give your opponent a better hand.
The rule of 4 is a linear approximation. The exact formula accounts for the conditional probability: if you miss the turn, the river has one fewer unseen card. For small outs counts the difference is negligible; for 15+ outs the rule of 4 slightly overstates your equity.
If your odds against are 2:1, you need the pot to offer at least 2:1 odds to call profitably. If you call 1 unit to win 2 units already in the pot, the pot odds match your odds against — a break-even call. More in the pot than 2 units? Positive-EV call.
Also known as
TG we-Calculate Editorial Team. (2026). Poker Odds Calculator — Outs & Draw Probability [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/poker-odds-calculator
TG we-Calculate Editorial Team. "Poker Odds Calculator — Outs & Draw Probability." TG we-Calculate. 2026. https://we-calculate.com/calculator/poker-odds-calculator.
TG we-Calculate Editorial Team, "Poker Odds Calculator — Outs & Draw Probability," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/poker-odds-calculator
@misc{wecalculate_poker_odds_calculator, title = {Poker Odds Calculator — Outs & Draw Probability}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/poker-odds-calculator}}, year = {2026}, note = {TG we-Calculate} }
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