Score differential calculator
The number each round turns into before it goes into your handicap.
Score differential calculator
One round, one number. This is what your handicap index is built from.
The score differential formula
A differential says how well you played that day, taking the course's difficulty into account. A 90 at a hard course can be a better differential than an 86 at an easy one. That's why your index uses differentials, not raw scores.
What goes into it
- Adjusted gross score: your score with each hole capped at net double bogey.
- Course rating: what a scratch golfer should shoot from your tees.
- Slope rating: how much harder the course plays for a bogey golfer than for a scratch golfer. 113 is average; the range is 55 to 155.
- PCC: the playing conditions adjustment. Usually 0. It runs from −1 to +3 on days when weather or setup made scores unusually high or low.
Examples
| Score | Rating | Slope | Differential |
|---|---|---|---|
| 78 | 72.4 | 131 | 4.8 |
| 86 | 70.1 | 118 | 15.2 |
| 90 | 73.6 | 139 | 13.3 |
| 95 | 68.9 | 112 | 26.3 |
| 104 | 71.5 | 127 | 28.9 |
The 90 at the hard course (13.3) beats the 86 at the easy one (15.2).
What to do with your differentials
Keep your last 20 and average the lowest 8. That's your handicap index. The handicap calculator keeps track of them for you.
More handicap tools
Common questions
What is a score differential in golf?
A number that shows how well you played one round once the course’s difficulty is taken out: (113 ÷ slope) × (adjusted score − course rating − PCC).
Can a score differential be negative?
Yes, if your adjusted score is lower than the course rating. Scratch and plus-handicap golfers have negative differentials often.
How do I work out a differential for 9 holes?
Use the 9-hole rating and slope, then add the expected differential for the other 9 based on your index. See the 9-hole handicap page.
Updated November 2026