Calculate your chances of improving your hand based on the cards on the board.
Your Hand
Ace
King
Queen
Jack
10
9
8
7
6
5
4
3
2
Hearts
Diamonds
Clubs
Spades
Ace
King
Queen
Jack
10
9
8
7
6
5
4
3
2
Hearts
Diamonds
Clubs
Spades
Community Cards (Board)
None
Ace
King
Queen
Jack
10
9
8
7
6
5
4
3
2
None
Hearts
Diamonds
Clubs
Spades
None
Ace
King
Queen
Jack
10
9
8
7
6
5
4
3
2
None
Hearts
Diamonds
Clubs
Spades
None
Ace
King
Queen
Jack
10
9
8
7
6
5
4
3
2
None
Hearts
Diamonds
Clubs
Spades
None
Ace
King
Queen
Jack
10
9
8
7
6
5
4
3
2
None
Hearts
Diamonds
Clubs
Spades
None
Ace
King
Queen
Jack
10
9
8
7
6
5
4
3
2
None
Hearts
Diamonds
Clubs
Spades
Your Odds of Improvement
Understanding Poker Odds and How to Use This Calculator
Poker is a game of skill, strategy, and probability. Understanding the odds of improving your hand is crucial for making informed decisions at the table. This calculator helps you quantify those chances, allowing you to assess whether to bet, call, or fold based on the potential of your hand.
What are Poker Odds?
In poker, odds refer to the probability of a specific event occurring, most commonly the probability of hitting a card that will improve your hand to a winning hand. These odds are typically expressed as a ratio, such as "3-to-1" against you. This means that for every 3 times the event doesn't happen, it's expected to happen 1 time.
How to Use This Poker Odds Calculator
This calculator focuses on the odds of improving your hand based on the cards currently visible to you: your two hole cards and the community cards (flop, turn, and river).
Your Hand: Select the rank and suit of your two hole cards. These are the cards dealt only to you.
Community Cards (Board): Select the rank and suit of the cards revealed on the table. You can input up to five community cards. If fewer than five cards are on the board (e.g., during the flop or turn), select "None" for the remaining cards.
Calculate Odds: Click the "Calculate Odds" button. The calculator will determine the number of "outs" (cards that can improve your hand) and then display the approximate odds of hitting one of those outs on the next card dealt.
The calculator provides odds for hitting *any* card that could improve your current hand to a better made hand (e.g., from a pair to two pair, from a straight draw to a straight, from a flush draw to a flush). It simplifies by not calculating specific hand rankings, but rather the general improvement potential.
The Math Behind the Odds (Simplified)
The core concept involves identifying your "outs" and then calculating the probability of drawing one of those outs.
Identifying Outs: An "out" is any card in the remaining deck that will improve your hand. For example, if you have two suited cards and four suited cards are already on the board (a flush draw), there are 9 remaining cards of that suit in the deck (13 total suits – 4 on board – 2 in your hand = 9 outs). If you have an open-ended straight draw (e.g., 6-7 and the board is 3-4-8-9), there are 8 outs (the four 5s and four 10s).
Calculating Probability:
To hit on the next card (e.g., Turn to River): The number of outs divided by the number of unknown cards remaining in the deck. If there are 47 unknown cards and 8 outs, the probability is 8/47.
To hit by the end of the hand (e.g., Flop to River): A common rule of thumb is to multiply your outs by 2 for the probability of hitting on the turn or river. So, 8 outs * 2 = approximately 16% chance.
This calculator uses a more precise method for the probability of hitting on the *next* card.
Example: If you have a flush draw with 9 outs and 47 unknown cards remaining in the deck, your chance of hitting your flush on the next card is 9 out of 47, which is approximately 19.1%. The odds against you are roughly 3.9 to 1 (47-9 = 38; 38:9 simplified).
When to Use This Calculator
This calculator is most useful in Texas Hold'em and Omaha poker, particularly when you are faced with a decision on the flop or turn. It helps you:
Assess Draw Strength: Quantify the potential of your draws (flush draws, straight draws).
Pot Odds Calculation: Compare your calculated pot odds (the ratio of the current pot size to the bet you need to call) with the odds of improving your hand. If your chances of winning are better than the pot odds, calling is often a profitable play.
Strategic Decisions: Make more confident decisions about betting, raising, calling, or folding.
Remember that poker involves more than just odds; opponent tendencies, betting patterns, and table image also play significant roles. However, a solid understanding of poker odds is a foundational skill for any serious player.
var ranks = ['2', '3', '4', '5', '6', '7', '8', '9', 'T', 'J', 'Q', 'K', 'A'];
var suits = ['H', 'D', 'C', 'S'];
function getCardId(index) {
return {
rankId: 'boardCard' + index + 'Rank',
suitId: 'boardCard' + index + 'Suit'
};
}
function updateAvailableCards() {
var usedCards = {};
function markCardUsed(rank, suit) {
if (!rank || !suit || rank === '0' || suit === '0') return;
var key = rank + suit;
usedCards[key] = true;
}
// Mark hole cards as used
markCardUsed(document.getElementById('holeCard1Rank').value, document.getElementById('holeCard1Suit').value);
markCardUsed(document.getElementById('holeCard2Rank').value, document.getElementById('holeCard2Suit').value);
// Mark board cards as used
for (var i = 1; i <= 5; i++) {
var cardIds = getCardId(i);
markCardUsed(document.getElementById(cardIds.rankId).value, document.getElementById(cardIds.suitId).value);
}
// Update options for board cards based on used cards
for (var i = 1; i <= 5; i++) {
var cardIds = getCardId(i);
var rankSelect = document.getElementById(cardIds.rankId);
var suitSelect = document.getElementById(cardIds.suitId);
var currentRank = rankSelect.value;
var currentSuit = suitSelect.value;
// Populate ranks
for (var j = 0; j < rankSelect.options.length; j++) {
var option = rankSelect.options[j];
if (option.value === '0') continue; // Skip 'None' option
var key = option.value + currentSuit;
if (usedCards[key] && option.value !== currentRank) {
option.disabled = true;
} else {
option.disabled = false;
}
}
// Populate suits
for (var j = 0; j < suitSelect.options.length; j++) {
var option = suitSelect.options[j];
if (option.value === '0') continue; // Skip 'None' option
var key = currentRank + option.value;
if (usedCards[key] && option.value !== currentSuit) {
option.disabled = true;
} else {
option.disabled = false;
}
}
}
}
function calculateOdds() {
var hc1Rank = document.getElementById('holeCard1Rank').value;
var hc1Suit = document.getElementById('holeCard1Suit').value;
var hc2Rank = document.getElementById('holeCard2Rank').value;
var hc2Suit = document.getElementById('holeCard2Suit').value;
var boardCards = [];
for (var i = 1; i <= 5; i++) {
var rankId = 'boardCard' + i + 'Rank';
var suitId = 'boardCard' + i + 'Suit';
var rank = document.getElementById(rankId).value;
var suit = document.getElementById(suitId).value;
if (rank !== '0' && suit !== '0') {
boardCards.push({ rank: rank, suit: suit });
}
}
var allCards = [];
var holeCards = [{ rank: hc1Rank, suit: hc1Suit }, { rank: hc2Rank, suit: hc2Suit }];
for (var r = 0; r < ranks.length; r++) {
for (var s = 0; s < suits.length; s++) {
allCards.push({ rank: ranks[r], suit: suits[s] });
}
}
var knownCards = [];
knownCards.push(holeCards[0]);
knownCards.push(holeCards[1]);
for (var i = 0; i < boardCards.length; i++) {
knownCards.push(boardCards[i]);
}
var deck = allCards.filter(function(card) {
for (var k = 0; k < knownCards.length; k++) {
if (card.rank === knownCards[k].rank && card.suit === knownCards[k].suit) {
return false;
}
}
return true;
});
var outs = 0;
var currentHand = holeCards.concat(boardCards);
// Helper function to get rank value for comparison
function getRankValue(rank) {
return ranks.indexOf(rank);
}
// Helper to check if a card is in the hand
function isCardKnown(rank, suit) {
for (var i = 0; i < knownCards.length; i++) {
if (knownCards[i].rank === rank && knownCards[i].suit === suit) {
return true;
}
}
return false;
}
// Simplified Outs Calculation: Counts cards that improve ANY part of a potential hand.
// This is a simplification, a full poker engine would evaluate best 5-card hand.
// We'll count cards that complete common draws (flush, straight) or improve pairs.
var holeRanks = [hc1Rank, hc2Rank];
var holeSuits = [hc1Suit, hc2Suit];
var boardRanks = boardCards.map(function(c) { return c.rank; });
var boardSuits = boardCards.map(function(c) { return c.suit; });
var rankCounts = {};
holeRanks.forEach(function(rank) { rankCounts[rank] = (rankCounts[rank] || 0) + 1; });
boardRanks.forEach(function(rank) { rankCounts[rank] = (rankCounts[rank] || 0) + 1; });
var suitCounts = {};
holeSuits.forEach(function(suit) { suitCounts[suit] = (suitCounts[suit] || 0) + 1; });
boardSuits.forEach(function(suit) { suitCounts[suit] = (suitCounts[suit] || 0) + 1; });
// Flush draw outs
for (var s = 0; s < suits.length; s++) {
var currentSuit = suits[s];
var suitCount = 0;
var cardsOfSuit = [];
for (var i = 0; i < holeCards.length; i++) {
if (holeCards[i].suit === currentSuit) {
suitCount++;
cardsOfSuit.push(holeCards[i]);
}
}
for (var i = 0; i = 4) { // Flush draw
outs += (13 – suitCount); // Total of that suit minus those already seen
}
}
// Straight draw outs
var distinctRanks = Array.from(new Set(holeRanks.concat(boardRanks)));
distinctRanks.sort(function(a, b) { return getRankValue(a) – getRankValue(b); });
var straightOuts = 0;
var straightSets = [];
// Try to find potential straight groups (max 5 cards needed)
var tempSet = [];
for(var i = 0; i 5) tempSet.shift(); // Keep window size to 5
if(tempSet.length >= 3){ // Need at least 3 cards to potentially form a straight with 2 outs
// Check for straight gaps
var currentStraight = [];
for(var k=0; k = 2){
var firstRankVal = getRankValue(currentStraight[0]);
var lastRankVal = getRankValue(currentStraight[currentStraight.length – 1]);
if(lastRankVal – firstRankVal === currentStraight.length – 1){
// Found a sequence, now count the missing cards
var missingCount = 0;
var potentialOuts = [];
for(var r_idx = firstRankVal; r_idx <= lastRankVal; r_idx++){
var rankToAdd = ranks[r_idx];
var isRankKnown = false;
for(var i=0; i < knownCards.length; i++){
if(knownCards[i].rank === rankToAdd){
isRankKnown = true;
break;
}
}
if(!isRankKnown){
potentialOuts.push(rankToAdd);
}
}
// Add the number of potential outs for this straight
// Avoid double counting if multiple paths lead to the same card
potentialOuts.forEach(function(potRank){
if(straightSets.indexOf(potRank) === -1){
straightSets.push(potRank);
}
});
}
}
}
}
// Special case for A-2-3-4-5 straight
var aceLowStraightPossible = false;
var aceLowCards = ['A', '2', '3', '4', '5'];
var numAceLowKnown = 0;
var potentialAceLowOuts = [];
for(var i=0; i < aceLowCards.length; i++){
var rankToCheck = aceLowCards[i];
var found = false;
for(var k=0; k = 2 && potentialAceLowOuts.length > 0){
potentialAceLowOuts.forEach(function(potRank){
if(straightSets.indexOf(potRank) === -1){
straightSets.push(potRank);
}
});
}
// Calculate outs for pairs improvement (three of a kind, two pair, full house)
var pairOuts = 0;
var setCounts = {}; // Count of cards for each rank
var counts = {};
holeCards.forEach(function(card) { counts[card.rank] = (counts[card.rank] || 0) + 1; });
boardCards.forEach(function(card) { counts[card.rank] = (counts[card.rank] || 0) + 1; });
for (var rank in counts) {
if (counts[rank] === 2) { // A pair
pairOuts += 2; // Two more cards to make three of a kind or a better pair
} else if (counts[rank] === 3) { // Three of a kind
pairOuts += 1; // One more card to make a full house
}
}
// Sum up unique outs
var allUniqueOuts = [];
// Add flush outs
for (var s = 0; s < suits.length; s++) {
var currentSuit = suits[s];
var suitCount = 0;
for (var i = 0; i < holeCards.length; i++) { if (holeCards[i].suit === currentSuit) suitCount++; }
for (var i = 0; i = 4) {
for (var r_idx = 0; r_idx < ranks.length; r_idx++) {
var rankToCheck = ranks[r_idx];
if (!isCardKnown(rankToCheck, currentSuit)) {
allUniqueOuts.push(rankToCheck + currentSuit);
}
}
}
}
// Add straight outs
for (var i = 0; i < straightSets.length; i++) {
var rankToCheck = straightSets[i];
for (var s_idx = 0; s_idx < suits.length; s_idx++) {
var suitToCheck = suits[s_idx];
if (!isCardKnown(rankToCheck, suitToCheck)) {
allUniqueOuts.push(rankToCheck + suitToCheck);
}
}
}
// Add pair improvement outs (only if they don't form a flush/straight)
// This part is tricky as a card might be both a straight out and improve a pair.
// We need to count unique cards. Let's re-approach by iterating through the deck.
var possibleImprovingCards = [];
for (var i = 0; i < deck.length; i++) {
var potentialCard = deck[i];
var tempHand = currentHand.concat([potentialCard]);
// This would require a full hand evaluation engine to be truly accurate.
// For this calculator's scope, we focus on common draws:
// 1. Cards that complete a flush draw.
// 2. Cards that complete a straight draw.
// 3. Cards that make trips or two pair from a single pair, or full house from trips.
// Check for flush completion
var flushSuit = null;
var flushCount = 0;
for(var j=0; j= 5){
if (possibleImprovingCards.indexOf(potentialCard.rank + potentialCard.suit) === -1) {
possibleImprovingCards.push(potentialCard.rank + potentialCard.suit);
}
}
// Check for straight completion
var tempRanks = tempHand.map(c => c.rank);
var tempDistinctRanks = Array.from(new Set(tempRanks)).sort(function(a, b) { return getRankValue(a) – getRankValue(b); });
// Check straight of length 5
for (var len = 5; len <= tempDistinctRanks.length; len++) {
for (var start = 0; start c.rank);
var numAceLowKnown = 0;
for(var k=0; k = 4 && aceLowTempRanks.includes(potentialCard.rank) && aceLowStraight.includes(potentialCard.rank)){
if (possibleImprovingCards.indexOf(potentialCard.rank + potentialCard.suit) === -1) {
possibleImprovingCards.push(potentialCard.rank + potentialCard.suit);
}
}
// Check for pair improvement (making trips, two pair, full house)
var rankCountsTemp = {};
tempHand.forEach(function(card) { rankCountsTemp[card.rank] = (rankCountsTemp[card.rank] || 0) + 1; });
for (var rank in rankCountsTemp) {
if (rankCountsTemp[rank] === 3 && rank === potentialCard.rank) { // Making trips from pair, or making full house from trips
if (possibleImprovingCards.indexOf(potentialCard.rank + potentialCard.suit) === -1) {
possibleImprovingCards.push(potentialCard.rank + potentialCard.suit);
}
} else if (rankCountsTemp[rank] === 2 && rank === potentialCard.rank) { // Making two pair or trips from pair
if (possibleImprovingCards.indexOf(potentialCard.rank + potentialCard.suit) === -1) {
possibleImprovingCards.push(potentialCard.rank + potentialCard.suit);
}
} else if (rankCountsTemp[rank] === 4) { // Making a full house from 3 of a kind
// This card completes the full house – already counted if rankCountsTemp[rank] was 3 before adding potentialCard.
// If the potentialCard itself creates the 4 of a kind, we don't count it as a strict improvement for this simplified calc.
}
}
}
outs = possibleImprovingCards.length;
var remainingCards = deck.length;
var resultElement = document.getElementById('result');
if (remainingCards === 0) {
resultElement.textContent = "Insufficient remaining cards to calculate.";
return;
}
if (outs === 0) {
resultElement.textContent = "0 Outs. 0% chance of improvement.";
return;
}
var percentage = (outs / remainingCards) * 100;
var oddsAgainstNum = remainingCards – outs;
var oddsAgainstDen = outs;
// Simplify odds ratio
var gcd = function(a, b) {
return b === 0 ? a : gcd(b, a % b);
};
var commonDivisor = gcd(oddsAgainstNum, oddsAgainstDen);
oddsAgainstNum /= commonDivisor;
oddsAgainstDen /= commonDivisor;
resultElement.textContent = percentage.toFixed(2) + "% (" + oddsAgainstNum + " to " + oddsAgainstDen + " against)";
}
// Initialize available cards on load
document.addEventListener('DOMContentLoaded', updateAvailableCards);