Golf Handicap Index Calculator
A golf handicap is a numerical measure of a golfer's ability, allowing players of different skill levels to compete fairly against each other. The World Handicap System (WHS), introduced in 2020, provides a unified method for calculating handicaps globally. This calculator helps you determine your Handicap Index based on your recent scores, course ratings, and slope ratings.
How Your Handicap Index is Calculated:
The WHS uses your best 8 Score Differentials from your most recent 20 scores. A Score Differential is calculated for each round using the following formula:
Score Differential = (Adjusted Gross Score – Course Rating – PCC Adjustment) × 113 / Slope Rating
For simplicity, this calculator does not include the Playing Conditions Calculation (PCC Adjustment), which is a daily adjustment based on how all golfers performed that day. It focuses on the core components:
- Adjusted Gross Score: Your score after applying any Equitable Stroke Control (ESC) or Net Double Bogey adjustments (which limit the maximum score you can take on any hole). For this calculator, you will input your adjusted gross score.
- Course Rating: A numerical value, typically between 67 and 77, representing the playing difficulty of a course for a scratch golfer (a golfer with a handicap of 0).
- Slope Rating: A numerical value, typically between 55 and 155, representing the relative difficulty of a course for a bogey golfer (a golfer with a handicap of approximately 20-24) compared to a scratch golfer. The average slope rating is 113.
After calculating the Score Differentials for each round, the system selects a certain number of your lowest differentials based on how many eligible scores you have submitted (e.g., best 1 of 3 scores, best 8 of 20 scores). These selected differentials are then averaged, and the result is truncated to one decimal place to give you your Handicap Index.
Enter Your Recent Round Data (Up to 20 Rounds):
Enter your Adjusted Gross Score, Course Rating, and Slope Rating for each of your most recent rounds. Leave fields blank for rounds you haven't played or don't wish to include.
Round 1
Round 2
Round 3
Round 4
Round 5
Round 6
Round 7
Round 8
Round 9
Round 10
Round 11
Round 12
Round 13
Round 14
Round 15
Round 16
Round 17
Round 18
Round 19
Round 20
Example Calculation:
Let's say you have 5 valid scores:
- Round 1: Score 85, Course Rating 72.0, Slope Rating 125
- Round 2: Score 82, Course Rating 71.5, Slope Rating 120
- Round 3: Score 88, Course Rating 73.0, Slope Rating 130
- Round 4: Score 80, Course Rating 70.5, Slope Rating 118
- Round 5: Score 83, Course Rating 72.5, Slope Rating 122
Differentials:
- Round 1: (85 – 72.0) * 113 / 125 = 11.752
- Round 2: (82 – 71.5) * 113 / 120 = 9.879
- Round 3: (88 – 73.0) * 113 / 130 = 13.038
- Round 4: (80 – 70.5) * 113 / 118 = 9.106
- Round 5: (83 – 72.5) * 113 / 122 = 9.725
Sorted Differentials: 9.106, 9.725, 9.879, 11.752, 13.038
For 5 scores, the WHS uses the lowest 1 differential.
Lowest Differential: 9.106
Handicap Index = 9.106 (no average needed for 1 score) = 9.1 (truncated to one decimal).
If we had more scores, say 8 scores, we would take the average of the best 3 differentials and then multiply by 0.96.
Disclaimer: This calculator provides an estimate of your Handicap Index based on the World Handicap System (WHS) formula, excluding the Playing Conditions Calculation (PCC). For an official Handicap Index, you must register with an authorized golf association in your region and submit scores through their approved system.
function calculateHandicap() { var differentials = []; var numRounds = 20; for (var i = 1; i 0) { var differential = (score – courseRating) * 113 / slopeRating; differentials.push(differential); } } var resultDiv = document.getElementById("result"); if (differentials.length = 3 && numScores = 6 && numScores = 8 && numScores = 10 && numScores = 12 && numScores = 14 && numScores = 16 && numScores <= 17) { numDifferentialsToUse = 7; } else if (numScores === 18) { numDifferentialsToUse = 8; } else if (numScores === 19) { numDifferentialsToUse = 9; } else if (numScores === 20) { numDifferentialsToUse = 8; // Best 8 of 20 for WHS } else { resultDiv.innerHTML = "An unexpected error occurred with the number of scores."; return; } var selectedDifferentials = differentials.slice(0, numDifferentialsToUse); var sumOfSelectedDifferentials = 0; for (var j = 0; j < selectedDifferentials.length; j++) { sumOfSelectedDifferentials += selectedDifferentials[j]; } var averageDifferential = sumOfSelectedDifferentials / selectedDifferentials.length; // Handicap Index = Average of selected differentials, truncated to one decimal place. // The WHS does NOT apply a 0.96 reduction factor to the Handicap Index itself. // The 0.96 factor was part of the old USGA system for calculating the Handicap Index. // WHS uses the average of the best differentials directly, then truncates. // Let's stick to the WHS standard for the final index. var handicapIndex = Math.floor(averageDifferential * 10) / 10; // Truncate to one decimal resultDiv.innerHTML = "Your estimated Handicap Index is: " + handicapIndex.toFixed(1) + ""; }