Golf Score Differential Calculator (Handicap)
By Santaji GadepatilinUpdated October 27, 2026
A golf score differential adjusts your score for course difficulty. It is the building block of the World Handicap System.
How to use the golf score differential calculator
Enter your adjusted gross score, the course rating and slope rating for your tees, and any PCC adjustment (usually 0). The score differential is calculated.
Golf score differential formula
Score differential = (113 ÷ slope) × (score − course rating − PCC)
Example
Score 92 on a course rated 71.2 with slope 128:
Differential = 113 ÷ 128 × 20.8 = 18.4
Average your best 8 differentials from the last 20 rounds for your Handicap Index.
How the World Handicap System works
- Calculate a score differential for each round (this calculator).
- Your Handicap Index is the average of the best 8 differentials from your most recent 20 rounds.
- Your Course Handicap for a given course and tee is:
Course Handicap = Handicap Index × (Slope ÷ 113) + (Course Rating − Par)
With a Handicap Index of 15.0 on a course with slope 128, rating 71.2 and par 72: 15 × 128 ÷ 113 + (71.2 − 72) = 16.2, rounded to 16.
Adjusted gross score
Before calculating, cap each hole at net double bogey: par + 2 + any handicap strokes you receive on that hole. This stops one disaster hole from distorting your handicap.
Fewer than 20 rounds
| Rounds | Differentials used |
|---|---|
| 3 | Lowest 1, minus 2.0 |
| 5 | Lowest 1 |
| 6 | Average of lowest 2, minus 1.0 |
| 8 | Average of lowest 2 |
| 10 | Average of lowest 3 |
| 15 | Average of lowest 5 |
| 20 | Average of lowest 8 |
Slope rating
Slope rating measures how much harder a course is for a bogey golfer than for a scratch golfer. 113 is the standard; courses range from 55 to 155.
Frequently asked questions
What is a score differential?
A measure of how well you played relative to the course's difficulty, adjusted to a standard slope of 113.
How is the Handicap Index calculated?
Under the World Handicap System, it is the average of the best 8 of your most recent 20 score differentials.
Where do I find course and slope rating?
On the scorecard or the club's website, for the tees you played.
What is a good golf handicap?
The average handicap index for men is around 14–16. Single figures (under 10) is good; under 5 is excellent.
How many rounds do I need for a handicap?
Under the World Handicap System, 54 holes (three 18-hole rounds) are enough to get an initial index.