Calculate your official World Handicap System (WHS) handicap by entering your recent score data.
Understanding Golf Handicap Calculation
A golf handicap is a numerical measure that allows golfers of different abilities to compete against each other on a more equitable basis. The World Handicap System (WHS) is the global standard for calculating and managing handicaps. This calculator helps you determine your Handicap Differential, which is a key component in calculating your overall Handicap Index.
How Handicap Differential is Calculated
The core of the WHS handicap calculation is the Handicap Differential. This is a standardized score that represents how well you played on a particular course on a specific day, adjusted for the difficulty of that course.
Adjusted Gross Score (AGS): This is your gross score, with adjustments for exceptional scoring (e.g., using the Net Double Bogey maximum score for each hole) according to WHS rules. For simplicity in this calculator, we use your raw score, assuming it's your AGS.
Course Rating: This is the evaluation of the playing difficulty of a course for scratch golfers and provides a barrier to each hole played. It is expressed as strokes taken to one decimal place, and the lower the number, the easier the course.
Slope Rating: This is the evaluation of the relative difficulty of a course for non-scratch golfers compared to scratch golfers. It ranges from 55 to 155, where 113 is the slope rating of an average difficulty course. A higher slope rating means the course is significantly harder for players who are not scratch golfers.
Calculating Your Handicap Index
Your Handicap Index is derived from your Handicap Differentials. The WHS typically considers your best 8 differentials from your most recent 20 scores. The Handicap Index is the average of these best 8 differentials.
The system is dynamic. As you post more scores, your Handicap Index will adjust to reflect your current playing ability more accurately.
Why Use a Handicap Index?
Fair Competition: It allows golfers of varying skill levels to compete against each other in tournaments and casual games.
Game Improvement Tracking: It provides a measurable way to track your progress and see how your game is improving over time.
Understanding Your Game: It gives you and others a clear indication of your typical playing standard.
Important Notes:
This calculator focuses on determining the Handicap Differential for a single round. To get your official Handicap Index, you would need to average the best 8 differentials from your last 20 scores.
For official handicap tracking and use in tournaments, you must register with a golf club affiliated with a golf association that follows the WHS.
The Adjusted Gross Score can sometimes be different from your actual score due to WHS adjustments (like Net Double Bogey). This calculator uses the score you enter directly as the AGS.
function calculateHandicap() {
var courseRating = parseFloat(document.getElementById("courseRating").value);
var slopeRating = parseFloat(document.getElementById("slopeRating").value);
var score = parseFloat(document.getElementById("score").value);
var currentHandicapIndex = parseFloat(document.getElementById("handicapIndex").value); // Optional
var resultDiv = document.getElementById("result");
resultDiv.style.display = "none"; // Hide previous result
// Input validation
if (isNaN(courseRating) || isNaN(slopeRating) || isNaN(score)) {
resultDiv.innerHTML = "Please enter valid numbers for Course Rating, Slope Rating, and Score.";
resultDiv.style.backgroundColor = "#dc3545"; // Red for error
resultDiv.style.display = "block";
return;
}
if (slopeRating <= 0) {
resultDiv.innerHTML = "Slope Rating must be a positive number.";
resultDiv.style.backgroundColor = "#dc3545"; // Red for error
resultDiv.style.display = "block";
return;
}
// Calculate Handicap Differential
var handicapDifferential = (score – courseRating) * (113 / slopeRating);
// Round to two decimal places as per WHS standard
handicapDifferential = Math.round(handicapDifferential * 100) / 100;
var resultText = "Your Handicap Differential: " + handicapDifferential.toFixed(2) + "";
if (!isNaN(currentHandicapIndex)) {
// If current handicap is provided, give context to the new differential
var newHandicapIndex = (currentHandicapIndex * 19 + handicapDifferential) / 20; // Simplified for example
newHandicapIndex = Math.round(newHandicapIndex * 100) / 100;
resultText += "(This differential, averaged with your previous ones, would influence your Handicap Index)";
} else {
resultText += "(This is your Handicap Differential for this round)";
}
resultDiv.innerHTML = resultText;
resultDiv.style.backgroundColor = "var(–success-green)"; // Green for success
resultDiv.style.display = "block";
}