Golf Handicap Calculator
body {
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
line-height: 1.6;
margin: 0;
padding: 20px;
background-color: #f8f9fa;
color: #333;
}
.golf-calc-container {
max-width: 800px;
margin: 20px auto;
background-color: #fff;
padding: 30px;
border-radius: 8px;
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.input-group {
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label {
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input[type="number"],
input[type="text"] {
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font-size: 1rem;
margin-top: 5px;
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padding: 12px 20px;
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font-size: 1.1rem;
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margin-top: 10px;
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#result {
margin-top: 30px;
padding: 20px;
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.article-section ul {
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.article-section li {
margin-bottom: 10px;
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.score-entry {
display: flex;
justify-content: space-between;
margin-bottom: 5px;
font-size: 0.9rem;
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.score-entry span {
padding: 0 5px;
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}
.score-entry:nth-child(even) {
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Understanding Your Golf Handicap
A golf handicap is a numerical measure of a golfer's potential ability. It allows players of different skill levels to compete against each other on a more equal footing. The World Handicap System (WHS) is the global standard for calculating and managing handicaps, designed to be more equitable and easier to understand.
How the Handicap is Calculated
The WHS uses a 'handicap index' which is calculated based on your recent scores. The process involves:
- Score Differentials: For each round played, a "score differential" is calculated. This adjusts your gross score for the difficulty of the course played (using Course Rating and Slope Rating). The formula is:
Score Differential = (Gross Score - Course Rating) * (113 / Slope Rating)
- Selecting Best Differentials: Your handicap index is calculated using the *lowest* score differentials from your most recent rounds. The number of differentials used depends on the total number of scores you have recorded. For example:
- 5 to 6 scores: Lowest 1 differential
- 7 to 8 scores: Lowest 2 differentials
- 9 to 10 scores: Lowest 3 differentials
- 11 to 12 scores: Lowest 4 differentials
- 13 to 14 scores: Lowest 5 differentials
- 15 to 16 scores: Lowest 6 differentials
- 17 to 18 scores: Lowest 7 differentials
- 19 to 20 scores: Lowest 8 differentials
(Note: The calculator below simplifies this by allowing you to specify how many of your *most recent* scores to consider, and it will automatically pick the best ones).
- Calculating Handicap Index: The handicap index is the average of the selected lowest score differentials.
Handicap Index = (Sum of selected Score Differentials) / (Number of selected Score Differentials)
Why Use a Golf Handicap?
- Fair Competition: It levels the playing field, allowing players of vastly different abilities to play in the same competition.
- Tracking Progress: It provides a clear metric to track your improvement over time.
- Playing in Tournaments: Most amateur golf tournaments require players to have an official handicap.
- Course Management: Understanding your handicap can help you play smarter golf and manage your expectations on the course.
Important Considerations:
The WHS requires a minimum of 54 holes (typically 3 rounds) to establish an initial handicap index. This calculator assumes you have entered enough scores for a meaningful calculation. Always refer to official WHS guidelines for the most accurate and up-to-date information.
var numScoresInput = document.getElementById("numScores");
var scoreInputsDiv = document.getElementById("scoreInputs");
var resultDiv = document.getElementById("result");
var handicapValueDisplay = document.getElementById("handicapValue");
var scoreSummaryDiv = document.getElementById("scoreSummary");
function updateScoreInputs() {
var numScores = parseInt(numScoresInput.value);
scoreInputsDiv.innerHTML = "; // Clear previous inputs
if (isNaN(numScores) || numScores 20) {
numScores = 20; // Default to 20 if invalid
numScoresInput.value = numScores;
}
for (var i = 0; i < numScores; i++) {
var roundNum = i + 1;
var inputGroup = document.createElement('div');
inputGroup.className = 'input-group';
var labelPrefix = "Round " + roundNum + ": ";
var scoreLabel = document.createElement('label');
scoreLabel.innerHTML = labelPrefix + "Your Score";
var scoreInput = document.createElement('input');
scoreInput.type = 'number';
scoreInput.id = 'score' + i;
scoreInput.placeholder = "e.g., 85";
scoreInput.min = "0";
scoreInput.addEventListener('input', function() {
// Ensure sibling inputs are updated if they exist
var currentInput = this;
var currentIndex = parseInt(currentInput.id.replace('score', ''));
var courseRatingInputId = 'courseRating' + currentIndex;
var slopeRatingInputId = 'slopeRating' + currentIndex;
var courseRatingInput = document.getElementById(courseRatingInputId);
var slopeRatingInput = document.getElementById(slopeRatingInputId);
if (courseRatingInput) courseRatingInput.value = currentInput.value; // Simple copy for now, could add more logic
if (slopeRatingInput) slopeRatingInput.value = currentInput.value; // Simple copy for now, could add more logic
});
var ratingLabel = document.createElement('label');
ratingLabel.innerHTML = labelPrefix + "Course Rating";
var ratingInput = document.createElement('input');
ratingInput.type = 'number';
ratingInput.id = 'courseRating' + i;
ratingInput.placeholder = "e.g., 72.5";
ratingInput.step = "0.1";
ratingInput.min = "0";
var slopeLabel = document.createElement('label');
slopeLabel.innerHTML = labelPrefix + "Slope Rating";
var slopeInput = document.createElement('input');
slopeInput.type = 'number';
slopeInput.id = 'slopeRating' + i;
slopeInput.placeholder = "e.g., 130";
slopeInput.min = "0";
inputGroup.appendChild(scoreLabel);
inputGroup.appendChild(scoreInput);
inputGroup.appendChild(ratingLabel);
inputGroup.appendChild(ratingInput);
inputGroup.appendChild(slopeLabel);
inputGroup.appendChild(slopeInput);
scoreInputsDiv.appendChild(inputGroup);
}
}
function calculateHandicap() {
var numScoresToUse = parseInt(numScoresInput.value);
var scoreDifferentials = [];
var validScoresCount = 0;
for (var i = 0; i 0) {
var scoreDifferential = (score – courseRating) * (113 / slopeRating);
scoreDifferentials.push({
differential: scoreDifferential,
score: score,
courseRating: courseRating,
slopeRating: slopeRating,
round: i + 1
});
validScoresCount++;
}
}
if (validScoresCount < 5) {
resultDiv.style.display = 'block';
handicapValueDisplay.textContent = "Not enough valid scores.";
scoreSummaryDiv.innerHTML = "";
return;
}
// Sort score differentials in ascending order
scoreDifferentials.sort(function(a, b) {
return a.differential – b.differential;
});
// Determine how many of the best differentials to use based on WHS rules for 20 scores
// This simplified calculator uses the number of scores *provided* to determine selection,
// but WHS rules are based on total recorded scores.
// For simplicity, we'll take the lowest N where N is determined by the *number of inputs*.
// A more robust calculator would store all scores and select based on the number of scores recorded.
var numberOfBestDifferentialsToAverage;
if (numScoresToUse <= 6) numberOfBestDifferentialsToAverage = 1;
else if (numScoresToUse <= 8) numberOfBestDifferentialsToAverage = 2;
else if (numScoresToUse <= 10) numberOfBestDifferentialsToAverage = 3;
else if (numScoresToUse <= 12) numberOfBestDifferentialsToAverage = 4;
else if (numScoresToUse <= 14) numberOfBestDifferentialsToAverage = 5;
else if (numScoresToUse <= 16) numberOfBestDifferentialsToAverage = 6;
else if (numScoresToUse <= 18) numberOfBestDifferentialsToAverage = 7;
else numberOfBestDifferentialsToAverage = 8; // For 19-20 scores
var bestDifferentials = scoreDifferentials.slice(0, numberOfBestDifferentialsToAverage);
var sumOfBestDifferentials = 0;
for (var j = 0; j < bestDifferentials.length; j++) {
sumOfBestDifferentials += bestDifferentials[j].differential;
}
var handicapIndex = sumOfBestDifferentials / bestDifferentials.length;
var finalHandicap = handicapIndex; // WHS index is the handicap
resultDiv.style.display = 'block';
handicapValueDisplay.textContent = finalHandicap.toFixed(2);
// Display summary of scores used
var summaryHtml = "
Scores Used for Calculation:
";
if (bestDifferentials.length > 0) {
for (var k = 0; k < bestDifferentials.length; k++) {
var diff = bestDifferentials[k];
summaryHtml += "
";
summaryHtml += "" + diff.round + ":";
summaryHtml += "Score: " + diff.score + "";
summaryHtml += "CR: " + diff.courseRating + "";
summaryHtml += "SR: " + diff.slopeRating + "";
summaryHtml += "Diff: " + diff.differential.toFixed(2) + "";
summaryHtml += "
";
}
summaryHtml += "Average of lowest " + bestDifferentials.length + " differentials:
" + (sumOfBestDifferentials / bestDifferentials.length).toFixed(2) + "";
} else {
summaryHtml += "No scores were selected for calculation.";
}
scoreSummaryDiv.innerHTML = summaryHtml;
}
// Initial setup when the page loads
updateScoreInputs();