Golf handicap calculator: World Handicap System Handicap Index from your score differentials (best 8 of 20), then course and playing handicap for any tee.
The lowest 8 of your last 20 score differentials give a Handicap Index of 12.2. On tees rated 71.8 with a slope of 131 and par 72, a 12.2 index is a course handicap of 14 and a playing handicap of 13 at 95%.
Score differentials by round
CountedNot counted
Rounds and score differentials Rows: 20
#
Adjusted score
Course Rating
Slope Rating
PCC
Differential
Counts
1
88
71.8
131
0
14
Yes
2
92
70.4
124
0
19.7
3
85
71.8
131
0
11.4
Yes
4
90
72.6
135
1
13.7
Yes
5
87
70.4
124
0
15.1
6
94
71.8
131
0
19.1
7
86
72.6
135
0
11.2
Yes
8
89
70.4
124
0
17
9
91
71.8
131
1
15.7
10
84
70.4
124
0
12.4
Yes
11
93
72.6
135
0
17.1
12
88
71.8
131
0
14
13
86
70.4
124
0
14.2
14
95
72.6
135
2
17.1
15
87
71.8
131
0
13.1
Yes
16
90
70.4
124
0
17.9
17
85
72.6
135
0
10.4
Yes
18
89
71.8
131
0
14.8
19
83
70.4
124
0
11.5
Yes
20
92
71.8
131
0
17.4
How it's calculated S
Score differential, round 20
131113×(92−71.8−0)=17.424→17.4
Each round is rounded to the nearest tenth, .5 upwards (Rule 5.1). The table lists every round.
Choose the differentials
20 differentials in the scoring record: Rule 5.2 counts the lowest 8.
Rounded to the nearest whole number, .5 upwards (Rule 6.1). A negative result is a plus handicap.
Playing handicap
13.9434×0.95=13.2462→13
The allowance is applied to the unrounded course handicap (Rule 6.2a).
About the golf handicap calculator
The World Handicap System turns each round into a score differential: (113 ÷ Slope Rating) × (adjusted gross score − Course Rating − PCC), rounded to the nearest tenth. The Handicap Index is the average of the lowest 8 of your most recent 20 differentials. With 3 to 19 differentials, Rule 5.2a's table sets how many count and subtracts 2.0 or 1.0 when there are only 3, 4 or 6. The course handicap for a set of tees is Handicap Index × (Slope Rating ÷ 113) + (Course Rating − par).
The default 20 rounds give differentials from 10.4 to 19.7; the lowest 8 average 12.2125, so the Handicap Index is 12.2. On a course rated 71.8 with a slope of 131 and par 72, that is a course handicap of 14 and a playing handicap of 13 at the 95% stroke-play allowance.
Enter adjusted gross scores, each hole capped at net double bogey, or paste differentials from a handicap app. Exceptional score reductions are not applied, because they need your index as it stood on each day.
How to calculate a golf handicap
Under the World Handicap System, each round's score differential is 113 ÷ Slope Rating × (adjusted gross score − Course Rating − PCC), rounded to a tenth. The Handicap Index averages the lowest 8 of your latest 20 differentials: a lowest-eight average of 12.2125 gives an index of 12.2.
Score differential, worked by hand
A score of 88 on tees with a Course Rating of 71.8 and a Slope Rating of 131, with no PCC:
Strokes over the rating: 88 − 71.8 − 0 = 16.2.
Scale to standard difficulty: 113 ÷ 131 × 16.2 = 13.974.
Round to a tenth: 14.0.
A Slope Rating of 113 is standard, so harder tees with a higher slope shrink the differential for the same strokes over the rating.
Rounding takes .5 upward: 89 on tees rated 70.4 with slope 124 gives exactly 16.95, which becomes 17.0. For a negative differential, upward means toward zero, so −1.55 becomes −1.5.
The score is your adjusted gross score, with each hole capped at net double bogey: par + 2 + any handicap strokes you receive there. Before you have an index, the cap is par + 5.
PCC, the playing conditions calculation, is a daily adjustment from −1 to +3 made when scores that day run unusually high or low. It is subtracted, so 90 on tees rated 72.6 with slope 135 gives 14.6 with PCC 0 and 13.7 with PCC +1.
How many differentials count?
Rule 5.2a sets the count for a record of 3 to 20 differentials:
3: the lowest 1, minus 2.0
4: the lowest 1, minus 1.0
5: the lowest 1
6: the average of the lowest 2, minus 1.0
7 or 8: the lowest 2
9 to 11: the lowest 3
12 to 14: the lowest 4
15 or 16: the lowest 5
17 or 18: the lowest 6
19: the lowest 7
20: the lowest 8
The Rules' own examples: differentials of 15.3, 15.2 and 16.6 give 15.2 − 2.0 = 13.2. Six differentials of 40.7, 42.4, 36.1, 45.9, 43.6 and 45.0 average 38.4 over the lowest two, so the index is 37.4.
Only the most recent 20 differentials count, and no index can exceed 54.0.
Soft cap and hard cap
Once a record has 20 scores, Rule 5.8 limits how fast the index can rise above your Low Handicap Index, the lowest index you held in the previous 365 days.
Soft cap: any rise beyond 3.0 counts at half. With a low of 8.6 and a calculated 12.2, the index is 8.6 + 3.0 + (12.2 − 8.6 − 3.0) ÷ 2 = 11.9.
Hard cap: the total rise can never exceed 5.0. With a low of 5.0, the soft cap gives 10.1, so the hard cap sets 10.0.
Course handicap and playing handicap
Course handicap = Handicap Index × Slope Rating ÷ 113 + (Course Rating − par), rounded to a whole number with .5 upward. A 12.2 index on tees rated 71.8, slope 131, par 72 gives 12.2 × 131 ÷ 113 − 0.2 = 13.943, so 14 strokes.
Playing handicap applies the format's allowance to the unrounded course handicap: 13.943 × 95% = 13.246, so 13. Appendix C of the Rules of Handicapping recommends:
95% for individual stroke play
100% for individual match play
85% for four-ball stroke play
90% for four-ball match play
Rounding the course handicap first can change the answer. An 8.6 index on tees rated 71, slope 125, par 71 has a course handicap of 9.513; 85% of it is 8.086, so 8. Taking 85% of the rounded 10 gives 8.5, a wrong 9 (USGA rounding FAQ).
A negative course handicap is a plus handicap, and .5 again rounds toward zero: −2.5 becomes −2, written +2.
Example handicaps
Scenario
Handicap Index
Course handicap
Playing handicap
Default
12.200000
14.000000
13.000000
Three official differentials
13.200000
15.000000
14.000000
Six score adjustment
37.400000
43.000000
41.000000
Soft cap
11.900000
14.000000
13.000000
Unrounded allowance
8.600000
10.000000
8.000000
Default: 20 rounds on three sets of tees, whose lowest 8 differentials average 12.2125.
Three official differentials and Six score adjustment are the two Rules examples above.
Soft cap: the same 20 rounds with a Low Handicap Index of 8.6.
Unrounded allowance: the 8.6 index at 85% on tees rated 71, slope 125, par 71.
Except for the last row, course and playing handicaps are for tees rated 71.8, slope 131, par 72, at 95%.
Entering rounds
One 18-hole round per line, oldest first. 88, 71.8, 131 is adjusted gross score, Course Rating and Slope Rating; a fourth number adds PCC, as in 90, 72.6, 135, 1.
A line with a single number is read as a score differential, such as one copied from a handicap app.
Use the ratings of the tees each round was played from, not the tees you play next.
For a 9-hole round, enter the 18-hole differential your handicap record shows for it.
Type a plus index as a negative number: +2.1 is −2.1.
Official index and common mistakes
Only an authorized club or golf association issues an official Handicap Index. This estimate leaves out exceptional score reductions, which depend on your index on the day of each round, and adjustments made by a handicap committee.
Entering gross scores without hole caps. A 9 on a par 4 where you receive one stroke counts as 7, net double bogey. Entering the raw 9 adds two strokes to the round.
Swapping Course Rating and Slope Rating. Slope is a whole number from 55 to 155; the Course Rating is close to par.
Using an old Low Handicap Index. The caps use the lowest index from the previous 365 days.
Checked against: Rules of Handicapping 2024, Clarification 5.2a/2: average of lowest two 38.4 − 1 = 37.4
Rules example: double rounding, index 8.6
Start from
My Handicap Index
Handicap Index
8.6
Course Rating of the tees you play
71
Slope Rating
125
Course par
71
Handicap allowance
85%
Course handicap before rounding
9.5133
Course handicap
10 strokes
Playing handicap
8 strokes
Checked against: Rules of Handicapping 2024, Clarification 6.2a/1: Course Handicap 9.5132…, Playing Handicap (85%) 8
Questions
How is a golf handicap calculated?
Each round becomes a score differential, (113 ÷ Slope Rating) × (adjusted gross score − Course Rating − PCC). The Handicap Index is the average of the lowest 8 of the most recent 20 differentials, rounded to the nearest tenth (Rules of Handicapping, Rule 5.2b). A score of 88 on a course rated 71.8 with a slope of 131 gives (113 ÷ 131) × 16.2 = 14.0.
How many rounds do you need for a handicap?
Scores from at least 54 holes, such as three 18-hole rounds (Rule 4.5). With 3 differentials the index is the lowest one minus 2.0; with 4 it is the lowest minus 1.0; with 5 the lowest; with 6 the average of the lowest 2 minus 1.0. The count used then rises to the lowest 8 of 20. The Rules' own example turns differentials of 15.3, 15.2 and 16.6 into an initial index of 13.2.
What is the difference between Handicap Index and course handicap?
The Handicap Index measures ability on a course of standard difficulty, Slope Rating 113. The course handicap is the number of strokes you get on a particular set of tees: Handicap Index × (Slope ÷ 113) + (Course Rating − par), rounded to a whole number with .5 rounded up (Rule 6.1). A 12.2 index on tees rated 71.8, slope 131, par 72 plays to 14.
What is the maximum score per hole for handicap purposes?
Net double bogey: par plus 2 plus any handicap strokes you receive on the hole (Rule 3.1b). A player getting one stroke on a par 4 can post no more than 7 there. Until you have a Handicap Index, the limit is par plus 5 (Rule 3.1a). The adjusted gross score is the total after these caps, and it is the figure that goes into the differential.
What are the soft cap and hard cap?
They limit how fast a Handicap Index can rise (Rule 5.8). If a new index is more than 3.0 above your Low Handicap Index from the previous 365 days, only half of the increase beyond 3.0 counts, and the total rise can never exceed 5.0. With a Low Handicap Index of 8.6 and a calculated 12.2, the soft cap gives 8.6 + 3.0 + 0.3 = 11.9.
About this calculator
SD=Slope113(AGS−CR−PCC)HI=lowest 8 of 20 SD,CH=HI×113Slope+(CR−par)
This calculator includes 8 worked examples with independently sourced answers. They run in the test suite, and you can run them here too.
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