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Golf handicap calculator
Work out your Handicap Index the way the World Handicap System does: a score differential for each round, then the average of your best ones. Enter up to 20 rounds, newest last.
An unofficial estimate. Your official Handicap Index is calculated by your golf association (GHIN in the US, your national union in Great Britain and Ireland), which also applies the day's playing conditions, caps and exceptional-score reductions.
How your Handicap Index is worked out
Each round becomes a score differential: how many strokes over the course rating you scored, scaled to a course of average difficulty (slope 113):
Score differential = (113 ÷ slope rating) × (adjusted gross score − course rating − PCC)
Your Handicap Index is the average of your lowest 8 differentials from your last 20 rounds. With fewer than 20, fewer count, and with 3 to 6 rounds a small adjustment applies:
| Scores in your record | Differentials used | Adjustment |
|---|---|---|
| 3 | Lowest 1 | −2.0 |
| 4 | Lowest 1 | −1.0 |
| 5 | Lowest 1 | 0 |
| 6 | Lowest 2 (average) | −1.0 |
| 7–8 | Lowest 2 (average) | 0 |
| 9–11 | Lowest 3 (average) | 0 |
| 12–14 | Lowest 4 (average) | 0 |
| 15–16 | Lowest 5 (average) | 0 |
| 17–18 | Lowest 6 (average) | 0 |
| 19 | Lowest 7 (average) | 0 |
| 20 | Lowest 8 (average) | 0 |
The result is rounded to one decimal place, and the highest Handicap Index is 54.0.
Where to find the numbers
- Course rating and slope rating are printed on most scorecards for each set of tees, and listed by golf associations. A course rating of 71.4 means a scratch golfer is expected to score about 71.4 from those tees.
- Adjusted gross score is your score after capping each hole at net double bogey (par + 2 + any strokes you receive). See a worked example.
- PCC (playing conditions calculation) is set by the handicap system after the day's scores are in: from −1 to +3. Leave it at 0 if you don't know it.
What this calculator leaves out
- Exceptional scores. A differential 7.0 or more below your index cuts your index by 1.0, and 10.0 or more below by 2.0. That needs your index on the day, so it isn't applied here.
- 9-hole rounds. The official system turns a 9-hole score into an 18-hole differential using an expected score it doesn't publish, so enter 18-hole rounds only.
- Caps are applied only if you enter your Low Handicap Index and 20 rounds.
Next: your strokes for today
Your Handicap Index travels; your course handicap doesn't. The course handicap calculator turns your index into strokes for the course and tees you're playing.