What is a golf handicap and how is it calculated?
A Handicap Index measures your demonstrated ability. Each round becomes a Score Differential = (113 ÷ Slope Rating) × (adjusted gross score − Course Rating − PCC). With 20 scores, your Handicap Index is the average of your lowest 8 of the most recent 20 differentials. Your Course Handicap = Handicap Index × (Slope ÷ 113) + (Course Rating − par).
The World Handicap System in one paragraph
Since 2020, the USGA and The R&A have run one World Handicap System (WHS). You post scores; each becomes a Score Differential adjusted for how hard the course is; your Handicap Index is calculated from your best recent differentials; and before you play, you convert the Index to a Course Handicap for the specific tees (Rules of Handicapping, Rule 5).
Step 1: adjusted gross score
For handicap purposes, the most you can count on any hole is net double bogey: par + 2 + any handicap strokes you receive on that hole (Rule 3.1). New golfers without an Index use par + 5.
Step 2: Score Differential
Score Differential = (113 ÷ Slope Rating) × (adjusted gross score − Course Rating − PCC adjustment), rounded to the nearest tenth (USGA FAQ). The playing conditions calculation (PCC) is applied by your handicap service when conditions made scoring unusually hard or easy; use 0 if you don't know it. Example: 95 on a course rated 70.1 / 125 gives (113 ÷ 125) × (95 − 70.1) = 22.5.
Step 3: Handicap Index
With 20 or more scores, average the lowest 8 of the most recent 20 differentials and round to a tenth. With fewer scores, fewer are used, with small adjustments (Rule 5.2):
| Scores in record | Differentials used | Adjustment |
|---|---|---|
| 3 | Lowest 1 | -2.0 |
| 4 | Lowest 1 | -1.0 |
| 5 | Lowest 1 | 0 |
| 6 | Average of lowest 2 | -1.0 |
| 7–8 | Average of lowest 2 | 0 |
| 9–11 | Average of lowest 3 | 0 |
| 12–14 | Average of lowest 4 | 0 |
| 15–16 | Average of lowest 5 | 0 |
| 17–18 | Average of lowest 6 | 0 |
| 19 | Average of lowest 7 | 0 |
| 20 | Average of lowest 8 | 0 |
The maximum Handicap Index is 54.0. Soft and hard caps limit how fast an Index can rise versus your Low Handicap Index, and exceptional scores trigger reductions; your official handicap service handles these.
Step 4: Course Handicap
Course Handicap = Handicap Index × (Slope Rating ÷ 113) + (Course Rating − par) (USGA FAQ; Rule 6.1). A Playing Handicap then applies the format's allowance.
Free golf handicap calculator (WHS formula)
Enter one round per line as score, Course Rating, Slope Rating (optional 4th value: PCC). Use your adjusted gross score. Oldest first; the most recent 20 are used. This is an unofficial estimate; your official Handicap Index comes from your golf association.
How to get an official Handicap Index
In the US, join a golf club recognized by your state or regional golf association (many offer clubs without a home course) and post scores through GHIN; elsewhere, your national association runs it. Find ratings for your tees with the GHIN course search. Then use it in match play or net stroke play, and see how scoring works. A rangefinder is a popular way to shave strokes on approach shots.
Frequently asked questions
What is a good golf handicap?
It depends on your goals. A Handicap Index under about 20 means you regularly score in the low 90s or better on an average course; single digits is a strong amateur.
How many rounds do you need for a handicap?
Scores totalling 54 holes, from any combination of 9- and 18-hole rounds, produce an initial Handicap Index.
Is a Handicap Index the same as a Course Handicap?
No. The Index is portable; the Course Handicap converts it into strokes for a specific course and set of tees.