Understanding Odds: How to Calculate Your Chances of Winning
Understanding Odds: How to Calculate Your Chances of Winning
by Nathaniel 12:24pm Jan 10, 2025

Understanding Odds: How to Calculate Your Chances of Winning
Understanding poker odds is crucial to making informed decisions during a game. By knowing your chances of winning a hand, you can evaluate whether it's worth betting, calling, or folding. Here’s how to calculate your odds of winning and how to use this information to your advantage.
1. Understanding Poker Odds Basics
Odds represent the likelihood of a particular outcome. In poker, the most common odds you’ll need to calculate are the odds of completing your hand (hitting your outs) on future streets (turn and river). There are two main types of odds you’ll work with: pot odds and implied odds.
2. Pot Odds
Pot odds compare the current size of the pot to the cost of a contemplated call, helping you determine if it’s worth calling based on your chances of winning.
Calculating Pot Odds:
Pot Odds Formula:
Pot Odds=Cost to CallSize of the Pot\text{Pot Odds} = \frac{\text{Cost to Call}}{\text{Size of the Pot}}Pot Odds=Size of the PotCost to Call
For example, if the pot is $100, and you need to call a $20 bet to stay in, your pot odds are:
20100+20=20120=0.17or17%\frac{20}{100 + 20} = \frac{20}{120} = 0.17 \quad \text{or} \quad 17\%100+2020=12020=0.17or17%
This means you need to have a hand with at least a 17% chance of winning to justify the call.
3. Outs and Odds of Completing Your Hand
When you're deciding whether to call or raise, you need to know the odds of hitting one of your outs—the cards that improve your hand. Here's how to calculate it:
Finding Your Outs:
Outs are the cards that can improve your hand. For example:
If you have four cards to a flush (4 suited cards), there are 9 remaining suited cards in the deck.
If you have an open-ended straight draw (8 possible cards), you have 8 outs.
Odds of Hitting an Out:
After the flop, there are 47 unknown cards (52 cards - 2 in your hand - 3 on the board). To calculate the chance of hitting your outs on the turn or river, use the following approximations:
On the Turn:
Odds of hitting your outs=Number of outsUnknown cards remaining\text{Odds of hitting your outs} = \frac{\text{Number of outs}}{\text{Unknown cards remaining}}Odds of hitting your outs=Unknown cards remainingNumber of outs For 9 outs on the flop:
947=0.191or19.1%\frac{9}{47} = 0.191 \quad \text{or} \quad 19.1\%479=0.191or19.1%
On the River(if you miss on the turn): Add the outs from the turn and the river (two opportunities to hit an out). The odds for hitting on the turn or river is approximately:
Total odds=Number of outs×2Unknown cards remaining\text{Total odds} = \frac{\text{Number of outs} \times 2}{\text{Unknown cards remaining}}Total odds=Unknown cards remainingNumber of outs×2
So for 9 outs:
9×247+46=1893≈19.4%\frac{9 \times 2}{47 + 46} = \frac{18}{93} \approx 19.4\%47+469×2=9318≈19.4%
4. Using the Odds to Make Decisions
To make the best decision, compare the pot odds to the odds of completing your hand.
Example Decision:
Pot Odds:If the pot is $120, and you need to call $20 to stay in, your pot odds are 17%.
Odds of Hitting Your Draw: If you have 9 outs and the odds of hitting one of those outs by the river are 19.4%, it’s profitable to call. Since your odds of hitting the draw (19.4%) are higher than the pot odds (17%), the call is mathematically correct.
When to Call or Fold:
Call:If the odds of completing your hand (based on your outs) are better than the pot odds (cost to call versus pot size), you should call.
Fold:If your chances of winning (based on outs) are lower than the pot odds,it’s best to fold.
5. Implied Odds
Implied odds take into account the future bets you can win if you hit your hand. Sometimes the pot odds might not justify a call, but the potential for future bets (if you hit your draw) makes it worthwhile.
For example, if you’re on a flush draw and your pot odds suggest it’s a marginal call, but you believe that if you hit your flush, you can win a large bet on the river, implied odds may justify the call.
6. Calculating Equity
Equity is your share of the pot based on your hand’s likelihood of winning. Here’s how to calculate it:
Equity Formula:Equity=Number of outsRemaining unknown cards×100\text{Equity}= \frac{\text{Number of outs}}{\text{Remaining unknown cards}} \times 100Equity=Remaining unknown cardsNumber of outs×100
Example:
If you have 9 outs (flush draw), and there are 47 unknown cards:
Equity=947×100=19.1%\text{Equity} = \frac{9}{47} \times 100 = 19.1\%Equity=479×100=19.1%
This means your hand has a 19.1% chance of winning the pot on the turn.
7. Odds and Probabilities Quick Reference:
Here’s a quick reference for some common poker odds:
Flush Draw (9 outs):19.1% on the turn, 35% by the river.
Open-ended Straight Draw (8 outs): 17% on the turn, 31.5% by the river.
Inside Straight Draw (4 outs): 8.5% on the turn, 16.5% by the river.
Two Pair or Trips (no draws): About 16-18% for a two-pair hand or trips to improve on the turn or river.
8. Final Tips for Using Odds:
Understand your range:Know the potential hands you could have and calculate odds based on that range.
Don’t be over-reliant on odds: While odds are crucial, poker is a game of incomplete information. Use your judgment and knowledge of opponents' tendencies.
Balance your play:Sometimes, it’s okay to make a play that doesn't mathematically make sense, especially if you're trying to induce a fold or confuse opponents.
