Golf Handicap Index Calculator
Estimate your World Handicap System index from your recent scores, course and slope ratings.
Golf Handicap Index Calculator
Enter your gross score, course rating and slope rating for up to 8 rounds. Your estimated index updates as you type.
| # | Gross score | Course rating | Slope rating | Differential |
|---|
Estimated Handicap Index
Enter at least one completed round to see your estimate.
For each completed round we calculate a score differential: (gross score minus course rating) multiplied by 113, divided by the slope rating. We then take the lowest differentials and apply a small adjustment that depends on how many rounds you have entered:
- 1 to 3 rounds: average the lowest 1 differential, then subtract 2.0
- 4 rounds: lowest 1, then subtract 1.0
- 5 rounds: lowest 1, no further adjustment
- 6 rounds: average the lowest 2, then subtract 1.0
- 7 or 8 rounds: average the lowest 2, no further adjustment
The result is rounded to one decimal place. Course rating defaults to 70.0 and slope rating to 113 (the standard baseline) where you leave them unchanged.
Estimate only. The official World Handicap System uses up to 20 recent rounds plus further adjustments, so your verified index may differ.