Use this calculator to determine your Golf Handicap Index based on your recent scores, course ratings, and slope ratings. The World Handicap System (WHS) uses a specific formula to ensure fair play across different courses and skill levels.
Understanding Your Handicap Index
Your Handicap Index is a measure of your demonstrated ability on a golf course. It allows golfers of different skill levels to compete fairly against each other. The calculation takes into account your gross scores, the difficulty of the courses you play (Course Rating), and how that difficulty affects different skill levels (Slope Rating).
Gross Score: Your total score for a round before any handicap adjustments. For handicap purposes, it's often recommended to use an "Adjusted Gross Score" where individual hole scores are capped (e.g., Net Double Bogey) to prevent a single bad hole from disproportionately affecting your handicap. For simplicity in this calculator, please enter your gross score, assuming any necessary adjustments for individual hole scores have already been made if you wish to be precise.
Course Rating: A numerical value that represents the playing difficulty of a course for a scratch golfer (a golfer with a zero handicap). It's typically expressed to one decimal place (e.g., 72.3).
Slope Rating: A numerical value that represents the relative difficulty of a course for a bogey golfer (a golfer with approximately a 20 handicap) compared to a scratch golfer. It ranges from 55 to 155, with 113 being the standard average.
How the Handicap Index is Calculated (WHS Simplified)
The calculation involves several steps:
Calculate Handicap Differential for each score: Handicap Differential = (Gross Score - Course Rating) * 113 / Slope Rating This formula normalizes your score based on the course's difficulty.
Select the best differentials: The WHS uses a specific number of your lowest (best) Handicap Differentials from your most recent 20 scores. The number of differentials used depends on how many valid scores you have submitted (e.g., 8 of 20, 3 of 8).
Average the selected differentials: The selected differentials are summed and then divided by the number of differentials used.
Apply the Handicap Allowance: This average is then multiplied by a Handicap Allowance factor, which is 0.96 under the WHS.
Truncate the result: The final number is truncated to one decimal place to give you your Handicap Index.
Enter Your Recent Scores (Up to 20 Rounds)
Please enter your Gross Score, Course Rating, and Slope Rating for each of your most recent rounds. Fill in as many as you have, starting from Round 1. The calculator will automatically use the appropriate number of your best differentials.
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 the following 5 valid scores:
Round
Gross Score
Course Rating
Slope Rating
Differential
1
85
71.5
128
(85 – 71.5) * 113 / 128 = 12.0
2
82
70.8
125
(82 – 70.8) * 113 / 125 = 10.1
3
90
72.1
130
(90 – 72.1) * 113 / 130 = 15.5
4
88
71.0
127
(88 – 71.0) * 113 / 127 = 15.1
5
84
70.5
122
(84 – 70.5) * 113 / 122 = 12.5
For 5 scores, the WHS uses the lowest 1 differential. In this case, the lowest is 10.1.
Handicap Index = 10.1 * 0.96 = 9.696
Truncated to one decimal place, your Handicap Index would be 9.6.