function calculatePokerOdds() {
var outs = parseFloat(document.getElementById('outs').value);
var street = document.getElementById('street').value;
var potSize = parseFloat(document.getElementById('potSize').value);
var callSize = parseFloat(document.getElementById('callSize').value);
var resultsDiv = document.getElementById('poker-results');
var adviceBox = document.getElementById('adviceBox');
if (isNaN(outs) || outs 22) {
alert("Please enter a valid number of outs (typically 0-21).");
return;
}
var winProb = 0;
if (street === 'flop') {
// Calculation: 1 – ((cards remaining – outs) / cards remaining * (cards remaining – 1 – outs) / (cards remaining – 1))
winProb = (1 – ((47 – outs) / 47 * (46 – outs) / 46)) * 100;
} else {
// Calculation: outs / 46
winProb = (outs / 46) * 100;
}
// Ratio calculation (Odds against)
var ratio = ((100 – winProb) / winProb).toFixed(2);
// Pot Odds calculation
var potOddsRequired = 0;
var isCallProfitable = false;
if (!isNaN(potSize) && !isNaN(callSize) && callSize > 0) {
// Pot odds = Call / (Total Pot + Call)
potOddsRequired = (callSize / (potSize + callSize)) * 100;
isCallProfitable = winProb >= potOddsRequired;
}
document.getElementById('equityResult').innerText = winProb.toFixed(2) + "%";
document.getElementById('ratioResult').innerText = ratio + " to 1″;
if (!isNaN(potOddsRequired)) {
document.getElementById('potOddsResult').innerText = potOddsRequired.toFixed(2) + "%";
if (isCallProfitable) {
document.getElementById('decisionResult').innerText = "Positive (+EV)";
adviceBox.innerText = "MATHEMATICAL CALL: Your equity is higher than the pot odds.";
adviceBox.style.backgroundColor = "#d4edda";
adviceBox.style.color = "#155724";
} else {
document.getElementById('decisionResult').innerText = "Negative (-EV)";
adviceBox.innerText = "MATHEMATICAL FOLD: Your equity is lower than the pot odds.";
adviceBox.style.backgroundColor = "#f8d7da";
adviceBox.style.color = "#721c24";
}
} else {
document.getElementById('potOddsResult').innerText = "N/A";
document.getElementById('decisionResult').innerText = "N/A";
adviceBox.innerText = "Enter Pot Size and Call Amount for EV analysis.";
adviceBox.style.backgroundColor = "#e2e3e5";
adviceBox.style.color = "#383d41";
}
resultsDiv.style.display = 'block';
}
Understanding Poker Hand Odds and Outs
In Texas Hold'em, making the right decision often comes down to a simple mathematical comparison: Equity vs. Pot Odds. This calculator helps you determine if a "call" is mathematically profitable in the long run by looking at your "outs" (the cards left in the deck that will improve your hand to a winner).
What are Poker "Outs"?
An "out" is any card that, if drawn, will likely make your hand the best at the table. For example:
Flush Draw: You have 4 cards of the same suit. There are 13 cards of each suit, so 13 – 4 = 9 outs.
Open-Ended Straight Draw: You have four cards in sequence (e.g., 8-9-10-J). Any 7 or Q completes the straight. There are four 7s and four Qs, giving you 8 outs.
Two Overcards: If you have A-K and the board is 2-5-7, any Ace or King gives you top pair. There are 3 Aces and 3 Kings left, totaling 6 outs.
The Rule of 2 and 4
While this calculator uses exact percentages, players often use a shortcut called the "Rule of 2 and 4":
On the Flop: Multiply your outs by 4 to get your approximate percentage of hitting by the river.
On the Turn: Multiply your outs by 2 to get your percentage of hitting on the river.
Pot Odds Explained
Pot odds are the ratio of the current size of the pot to the cost of the contemplated call. If the pot is 100 and your opponent bets 50, the total pot is now 150. It costs you 50 to call. Your pot odds are 50 / (150 + 50) = 25%. If your chance of winning (equity) is higher than 25%, you should call.
Common Outs Reference Table
Hand Drawing To
Outs
Equity (Flop to River)
Straight Flush Draw
15
54.1%
Flush Draw
9
35.0%
Open-Ended Straight
8
31.5%
Inside Straight (Gutshot)
4
16.5%
Calculation Example
Imagine you have a Flush Draw (9 outs) on the flop. The pot is 200 and your opponent bets 100.
Your Equity: Approximately 35% to hit by the river.
Pot Odds: You need to call 100 to win a total pot of 400 (200 + 100 bet + 100 your call). 100/400 = 25%.
Decision: Since 35% (Equity) is greater than 25% (Pot Odds), calling is a profitable (+EV) play.