A handicap index is a portable number that represents your demonstrated golfing ability. It's worked out from your recent rounds and stays the same wherever you go — then converts into a "course handicap" for the specific course and tees you play on the day.
Think of your index as your golfing passport. A 12.4 index means the same thing at your home club as it does on holiday — the system adjusts for how hard each course is so the number stays fair everywhere.
How it's calculated
Every round you submit produces a score differential — a measure of how that round compared to the difficulty of the course you played (using its course rating and slope rating). Your index is then:
The average of the best 8 of your most recent 20 score differentials. Because only your better rounds count, your index reflects what you're capable of on a good day — not your average, and certainly not your worst.
That's the heart of the World Handicap System. Submit a great round and a low differential drops into your best-8, nudging your index down; the effect fades as newer rounds replace it.
Index vs course handicap
| Handicap index | Course handicap | |
|---|---|---|
| What it is | Your portable ability number | The actual shots you get today |
| Changes with the course? | No — same everywhere | Yes — depends on tee & difficulty |
| Used for | Storing & comparing ability | Allocating shots in a round |
The conversion is: Course Handicap = Index × (Slope ÷ 113) + (Course Rating − Par). You'll almost never do this by hand — a chart, app or league tool handles it.
What's a good handicap index?
- Scratch (0 or below) — elite amateur level.
- Single figures (under 10) — a strong, consistent player.
- Around 14 (men) / 27 (women) — roughly the global average.
- 28–54 — newer players; the maximum index is 54.0 to keep golf welcoming.
Track your form like a handicap index
Four Putt's Handicap Insight estimates a WHS-style index from your scored rounds, so you can see if you're playing above or below your number. Free for a small group.
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