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Handicap Index Calculator

Calculate your World Handicap System (WHS) index. We use the official formula: (Score - Course Rating) x 113 / Slope Rating.

Your Scores

0 / 20 Rounds

Recent Rounds (Best 8 count)

Score Rating Slope Differential Action
No scores added yet. Add at least 3 scores to get an initial index.

Estimated Index

N/A

Under the WHS, your index is calculated using your lowest 8 score differentials from your most recent 20 scores. If you have fewer than 20 scores, a sliding scale is used.

Related Tools

The Mathematics of the World Handicap System

The World Handicap System (WHS) was implemented in 2020 to unify six different handicap systems used around the world. The core equation is simple, but its application requires consistent data tracking.

How the Differential is Calculated

For every round you play, a Score Differential is calculated. This is not your score relative to par. It is your score relative to the difficulty of the course. The formula is:

(Adjusted Gross Score - Course Rating) x 113 / Slope Rating
  • Course Rating: What a scratch golfer (0.0 index) should score on that course.
  • Slope Rating: The relative difficulty of a course for a bogey golfer compared to a scratch golfer. The standard difficulty slope is 113.

Common Mistakes

Amateurs frequently miscalculate their handicap by simply taking their average score over par. If you shoot 85 on a Par 72, you are not a 13 handicap. If that course has a rating of 70.0 and a slope of 120, your differential for that round is 14.1.

Furthermore, the WHS uses a maximum hole score of Net Double Bogey for handicap purposes. You cannot record an '11' on a Par 4 and let it blow up your index. You must adjust your gross score down to the Net Double Bogey limit before calculating the differential.