Course Handicap Calculator
Course Handicap from Handicap Index, slope, rating, and par per WHS rules.
What it does
A Handicap Index travels, but strokes must fit the tees in front of you: 12.5 plays differently from championship tees than from the forward markers. Course Handicap makes that conversion with slope and the rating minus par gap.
The tool above takes index, slope, rating, and par. It returns the rounded Course Handicap, the exact figure, and the target score.
The default 12.5 index on 130 slope at 71.2 over par 72 gives 14 (13.6 exact) with target 86. A 20 index on standard 113 slope at 70 over 72 gives 18.
Formula follows USGA Course Handicap pages with the Rules of Handicapping FAQ behind them. Both state the same slope over 113 plus rating minus par form used here.
How to use
- Enter the Handicap Index.
- Enter the tee Slope Rating.
- Enter the tee Course Rating.
- Enter the tee par.
- Read Course Handicap first.
- Add par for the target score.
Formula
- Index
- Player Handicap Index, plus as negative.
- Slope
- Tee Slope Rating, 55 to 155.
- Rating
- Tee Course Rating for scratch.
- par
- Tee par for 18 (or 9) holes.
Standard slope is 113, which normalizes difficulty across courses. Rounding runs last to the nearest whole number for net double bogey use; Playing Handicap allowances start from the unrounded figure. Plus handicaps enter negative.
Worked example
Example: 12.5 index on tough tees
Defaults: 12.5 index, 130 slope, 71.2 rating, par 72.
- Index 12.5 x slope 130 / 113 = 14.3805.
- Rating minus par: 71.2 - 72 = -0.8.
- Exact: 14.3805 - 0.8 = 13.5805.
- Rounded: 13.5805 rounds to 14.
- Target: 14 + 72 = 86.
- Keep 13.6 for Playing Handicap allowances.
- Tool shows 14, 13.6 unrounded, Target 86.
Reference table
| Index | Slope / Rating / Par | Handicap |
|---|---|---|
| 12.5 | 130 / 71.2 / 72 | 14 (13.6 exact) |
| 20.0 | 113 / 70.0 / 72 | 18 |
| 5.0 | 145 / 73.1 / 72 | 8 (7.5 exact) |
| 0.0 | 113 / 72.0 / 72 | 0 (scratch) |
Limits
- 18-hole math shown; 9-hole halves index first.
- Allowances and formats sit outside.
- Scores need PCC and net double bogey steps.
- Committee ratings override estimates.
Common mistakes
- Dropping the rating minus par term.
- Rounding before allowances.
- Using differential math for tees.
- Comparing raw indexes across courses.
- Forgetting 9-hole halving.
Try it yourself
Quick checks. Answers sit tucked under each question.
20 index, 113 slope, 70 rating, par 72?
20 x 1 + (70 - 72) = 18. Target 90.
5 index, 145 slope, 73.1 rating, par 72?
5 x 145/113 = 6.42 + 1.1 = 7.52 rounds to 8. Target 80.
Plus 2.5 index as -2.5, 130 slope, 72 rating, par 72?
-2.5 x 130/113 = -2.88 rounds to -3. Target 69.
Questions
What is the Course Handicap formula?
Handicap Index x (Slope / 113) + (Rating - par), rounded to the nearest whole number.
Is this the same as a differential?
No. Differentials feed the index; Course Handicap spends it on a specific set of tees.
Can I compare tees with it?
Yes, exactly the point: the rating minus par term ports your index across tees.
What is Playing Handicap then?
Course Handicap x allowance, rounded last. Keep the unrounded figure for that step.
What is my target score?
Target = Course Handicap + par. Expect to hit it 20 to 25% of rounds.
What about 9-hole rounds?
Halve the index to one decimal, then apply 9-hole rating, slope, and par.