A handicap differential is computed from four elements: adjusted gross score, USGA Course Rating, USGA Slope Rating and 113 (the Slope Rating of a course of standard difficulty). To determine the handicap differential, subtract the USGA Course Rating from the adjusted gross score; multiply the difference by 113; then divide the resulting number by the USGA Slope Rating. Round the final number to the nearest tenth.
Handicap Differential =
(Adjusted Gross Score  USGA Course Rating) x 113 / USGA Slope Rating
a. Plus Handicap Differential
When the adjusted gross score is higher than the USGA Course Rating, the handicap differential is a positive number. Following is an example for determining a differential using an adjusted gross score of 95 made on a course with a USGA Course Rating of 71.5 and a USGA Slope Rating of 125:
Adjusted Gross Score  USGA Course Rating: 

95  71.5 = 23.5 
Difference x Standard Slope: 

23.5 x 113 = 2655.5 
Result / USGA Slope Rating: 

2655.5 / 125 = 21.24 
Handicap Differential (rounded): 

21.2 
b. Minus Handicap Differential
When the adjusted gross score is lower than the USGA Course Rating, the handicap differential is a negative number. Following is an example for determining a differential using an adjusted gross score of 69 made on a course with a USGA Course Rating of 71.5 and a USGA Slope Rating of 125:
Adjusted Gross Score  USGA Course Rating: 

69  71.5 = 2.5 
Difference x Standard Slope: 

2.5 x 113 = 282.5 
Result / USGA Slope Rating: 

282.5 / 125 = 2.26 
Handicap Differential (rounded): 

2.3 
