What is the score differential formula?

Score Differential = (113 / Slope Rating) × (Adjusted Gross Score − Course Rating − PCC). The result is rounded to one decimal place. It normalises a round to a standard-difficulty course so rounds from different tees and courses can be averaged fairly.

What is the 113 in the formula?

113 is the slope rating of a course of standard playing difficulty. Dividing 113 by the actual slope scales your score adjustment to that standard, so a round on a harder, higher-slope course is not penalised relative to an easier one.

What is the PCC adjustment?

PCC is the Playing Conditions Calculation, a daily adjustment between −1 and +3 that the WHS applies when scores across a course show that conditions were unusually hard or easy. Most rounds have a PCC of 0, so leave it at zero unless your association published a value for the day.

What is adjusted gross score?

It is your gross score after capping each hole at net double bogey — par plus two strokes plus any handicap strokes you receive on that hole. This limits the damage of a single blow-up hole so one disaster does not distort your handicap.

How is the Handicap Index built from differentials?

The WHS averages your lowest 8 score differentials from your most recent 20 rounds to produce your Handicap Index. Each round you post contributes one differential, so this calculator gives you the building block of the full index.

Golf Score Differential Calculator

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Every round you post under the World Handicap System is reduced to a single number — the score differential — before it can be averaged into your Handicap Index. This calculator applies the official WHS formula so you can see exactly what a round contributes, comparing fairly across tees, courses, and conditions.

How it works

The differential normalises your round to a standard-difficulty course:

Score Differential = (113 / Slope Rating) × (AGS − Course Rating − PCC)

AGS is your adjusted gross score (each hole capped at net double bogey), the course rating and slope come from the tees you played, and PCC is the daily Playing Conditions Calculation (usually 0). The result is rounded to one decimal place.

Example and tips

A round of 85 on a course rated 71.2 with a slope of 131 and a PCC of 0 gives (113 / 131) × (85 − 71.2 − 0) = 0.863 × 13.8 ≈ 11.9. That 11.9 is the figure the WHS averages with your other rounds. Always cap blow-up holes at net double bogey before entering the score, or the differential — and your index — will be inflated.