Handicap Index: A portable measure of your playing ability. Lower is better — a 10.0 index means you typically shoot about 10 strokes over a scratch golfer on a course of average difficulty.
Best Differential: Your lowest single-round differential, representing your best performance relative to course difficulty. The WHS system focuses on your best rounds, not your average.
Average Differential: The mean of your best selected differentials. The handicap index is 96% of this average, which slightly favors your better rounds.
Number of Rounds: How many valid rounds were used. The more rounds you enter, the more reliable your handicap estimate becomes.
How This Calculator Works
You enter each round's gross score, the course rating (CR), and slope rating. The tool computes a differential for each round as (Score − CR) × 113 ÷ Slope. It selects the best differentials based on how many rounds you've entered, averages them, and multiplies by 0.96 to produce the handicap index.
Quick Questions
What are course rating and slope rating?
Course rating is the expected score for a scratch golfer on that course. Slope rating measures relative difficulty for a bogey golfer versus a scratch golfer, on a scale of 55–155 (113 is average). Both are printed on most scorecards.
How many rounds do I need for a reliable handicap?
The WHS allows a handicap with as few as 3 rounds, but accuracy improves significantly with 10–20 rounds. With fewer rounds, the system uses fewer differentials and applies larger adjustments.
Why is the result multiplied by 0.96?
The 0.96 factor (sometimes called the "bonus for excellence") slightly lowers your index to better reflect your potential ability rather than your average. It encourages golfers to play to their best.
Is this an official WHS handicap?
No. An official handicap index must be issued through an authorized golf association (like the USGA in the US). This calculator uses the same formula but isn't connected to the official system or its additional adjustments.