In this article we consider the Slope Rating. It’s a key number within the World Handicap System (WHS) that is part of the calculation used for determining a player’s Course Handicap, which varies according to which set of tees you are playing from at any given course.
What is Slope Rating?
Slope Rating is described by the USGA as demonstrating the “measurement of the relative playing difficulty of a course for players who are not scratch golfers, compared to scratch golfers”. The higher a course’s Slope Rating, the higher the expected difference of scoring between a scratch golfer and a bogey golfer. The Slope Rating is not purely an indication of a course’s difficulty, it is an indication of the difference in difficulty for scratch and bogey players.
How is Slope Rating Calculated?
To determine the Slope Rating for a course requires two key numbers – Course Rating and Bogey Rating. The Course Rating is the evaluation of the playing difficulty of a golf course for the scratch player (0 handicap). The Bogey Rating is the evaluation of the difficulty of a course for a bogey player of 20-24 handicap.
Course and Bogey Rating are calculated using the USGA Course Rating System. Course rating teams consider more than 460 variables on a standard course rating, from each set of tees.
The USGA Course Rating System takes into account: the actual measured length of a golf course, factors that can affect the playing length of the course and other challenges that influence the playing difficulty of each hole called 'obstacle factors'. For example, do any 'crossing obstacles' demand long carries; are the fairways particularly narrow with trees, penalty areas, rough or bunkers in close proximity? Slope Rating is calculated by subtracting the Course Rating from the Bogey Rating and multiplying it by a constant.
What Does a Slope of 113 Mean?
113 is the average Slope Rating signifying a course of standard relative difficulty. The number 113 is used in calculating a player’s Course Handicap. Each player with a WHS Handicap Index can calculate their Course Handicap for any course by dividing the Slope Rating of that course by 113, multiplying that number by their Handicap Index and then adding in Course Rating minus Par for the set of tees they'll be playing from.
So, expressed as a mathematical formula, your Course Handicap for any given round from any given set of tees equals...
Handicap Index x Slope Rating/113 + (Course Rating - Par)
The final additional element of 'Course Rating - Par' has been part of the calculation for some handicap jurisdictions around the world for some time with the UK&I embracing it from the 2024 WHS revisions.
