⛳ Golf Handicap Calculator
Enter your score, the course rating, and the slope rating to calculate your score differential using the standard formula: (Score − Course Rating) × 113 ÷ Slope Rating.
The score differential formula
One round produces one score differential, which is your score measured against the course's difficulty rather than against par:
Differential = (Adjusted Score - Course Rating) × 113 / Slope RatingThe 113 is the slope of a course of average difficulty, so it is the yardstick everything is converted back to. Shoot 90 on a course rated 72.0 with a slope of 113 and the differential is exactly 18.0. Shoot 92 on a harder track rated 70.4 with a slope of 128 and it is (92 - 70.4) × 113 / 128 = 19.1 - two strokes worse on the card, only one worse once the course is accounted for.
Reading the two ratings off the card
- Course rating is what a scratch golfer is expected to shoot from that tee, printed to one decimal. It is often below par on a short course and above it on a long one, so do not substitute par for it.
- Slope rating runs from 55 to 155 and describes how much harder the course gets for a bogey golfer than for a scratch one. High slope shrinks your differential; low slope inflates it.
- Use the numbers for the tees you played - every set of tees carries its own pair.
Frequently asked questions
How many rounds do I need for a golf handicap?
54 holes, so three 18-hole rounds or any mix adding up to it. With three rounds your index is the lowest differential minus 2.0; the best 8 of 20 rule takes over at 20 scores.
What does a slope rating of 113 mean?
Average difficulty. At 113 the multiplier is 1, so the differential is simply your score minus the course rating.
Is course rating the same as par?
No. Par is set by hole length alone; course rating is measured from expected scratch scoring and can sit a stroke or two either side of par.