How score differential calculator Works
The differential formula
(Adjusted gross score − course rating) × 113 ÷ slope rating. The course rating is what a scratch golfer shoots; the slope (55–155, standard 113) measures difficulty for the rest of us. The differential expresses the round in portable units — comparable across every course on earth.
Adjusted gross score and the double-bogey cap
WHS caps any hole at net double bogey (par + 2 + handicap strokes) before computing — the 12 on the par-4 counts as an 8, protecting the index from single-hole disasters. This is why posting honestly IMPROVES most handicaps: the blow-ups are already forgiven by the formula.
The best-8-of-20 average
The WHS index averages your best 8 differentials of the last 20 rounds — rewarding peak form rather than average performance, and ignoring the worst days entirely. Post everything (the system expects it), and the index tracks capability rather than consistency.