There are lots of articles about the World Handicap System (WHS). I’ve found many of them confusing and/or long. Here’s my simple short guide, which includes a free Score Differential Calculator to download here.
What is the Golf World Handicap System?
The WHS Index (Golf Handicap) is a reflection of your ability. It is a global system, meaning you can play anyone, anywhere in the world and have a competitive game. Having one also opens the door to enter competitions (check out HowDidIDo).
How do I get a WHS Golf Handicap?
Club Members
- Hand in 54 holes of completed golf, making sure they are signed by a fellow member/playing partner and correctly completed (for help see Your Golf Scorecard Explained).
- The 54 holes can be any combination of 18 or 9 holes, e.g:
- 3 x 18 holes = 54 holes
- 6 x 9 holes = 54 holes
- 2 X 18 holes, 2x 9 holes = 54 holes
- The 54 holes can be any combination of 18 or 9 holes, e.g:
- Make sure you have signed up to the appropriate app in your country, so you can submit future rounds.
Non-Club Members
If you are not a club member, but live in the UK, you can get an official WHS Handicap, follow this link Handicap For Non-Members to find out how.
Your WHS Handicap
Once you have your WHS Handicap, you’ll see something like the image below.
The green filled circles in the chart show the best 8 scoring rounds from the most recent 20 rounds played. These can be a mixture of 9 or 18 holes. Each will count as a single round. The latest qualifying round is shown under “Scores” at the top, in this case:
- Adjusted Score is 43, highlighted by filled the green circle
- WHS Index is 11.9; this is your WHS handicap before you start the round
- Score Diff (Score Differential) is 14.0 (in this case it is equivalent 18-hole differential, calculated from the 9-holes played)
You may be wondering why the handicap went down from 11.9 to 11.8. This is because the new round played has qualified as one the best 8 rounds played. As a result the latest round of 43 qualifies and forms part of the WHS handicap calculation. If your WHS goes up, this is because a score that qualified before is no longer valid, i.e., it occurred 21 rounds ago. Another score is being used instead that has a higher Score Differential.
The only thing left to explain is Score Differential and how it is calculated. This is fairly complicated. If you’re keen and want to find out the inner workings of the calculation, continue reading and you will find a our free downloadable Score Differential Calculator (for 18 and 9 holes).
Score Differential Calculation Explained
Score Differential is a calculated measure of your score that is then used to calculate your WHS Index (providing it is one of your best 8 rounds in the last 20). You can use the below excel file to calculate this for 9 or 18 hole rounds:
Score Differential Calculation for 18-hole Rounds
For 18-hole rounds the Score Differential calculation is fairly straightforward (illustrated below). It requires the Slope Rating of the course played (SL or SR), your adjusted score, and the Course Rating (CR). The number 113 is a constant and shouldn’t be changed.
Adjusted Score Explained
Adjusted Score takes into account blow-up holes. For a player with a course handicap of 18, scores will be adjusted down to triple bogeys, e.g.:
- Par 3
- Player scores 7
- Expected score for 18 handicap score is 4
- Plus 2 shots = 6
- Score is adjusted down to 6
- Par 4
- Player scores 9
- Expected score for 18 handicap is 5
- Plus 2 shots = 7
- Score is adjusted down to 7
- Par 5
- Player scores 12
- Expected score for 18 handicap is 6
- Plus 2 shots = 8
- Score is adjusted down to 8
This is repeated for all holes and the final adjusted score calculated for the round. In the example below, the final adjusted score is 47, down from 49. The star (*) to the left of 47 highlights an adjusted score from the value shown in brackets.
Score Differential Calculation for 9-hole Rounds
The 9-hole score differential calculation is the same as the 18 hole calculation as above, except substituting your Course Rating and Adjusted Scores into the calculation: your 9-hole Course Rating, Adjusted Score and Score Differential will be about half that of an equivalent round over 18 holes. The Slope rating will be similar to an 18 hole value, e.g., 128.
The 9-hole score differential calculation becomes very complicated if you’re wanting to see an 18-hole Equivalent Score Differential, it’s not as straightforward as simply multiplying by 2. This is likely shown on your app for 9-hole rounds (see Figure 1) and may cause some confusion. There are essentially three steps to this calculation:
- Calculate your 9-hole Score Differential (as above).
- Calculate your 9-hole course handicap (or use a WHS app if it has this option)
- Use the above to calculate the 18-hole equivalent Score Differential
I hope you find this blog informative. If you have any questions or comments add them below or get in touch via twitter @howismygolf.
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