Why Two Ratings Are Necessary
If you look at any physical golf scorecard, next to each set of tees (Blue, White, Red, etc.), you will see two key numbers: Course Rating (e.g., 71.4) and Slope Rating (e.g., 128). While many casual golfers assume these numbers measure the same thing, they actually evaluate two entirely different aspects of course difficulty.
What Is Course Rating?
Course Rating evaluates the difficulty of a golf course for a scratch golfer (someone with a 0.0 Handicap Index) under normal weather conditions. It is expressed as a decimal score relative to par.
For example, if a course has a Par of 72 but a Course Rating of 73.8 from the back tees, a scratch golfer is expected to shoot around a 74 on an average day. If the rating is 69.5, the course plays noticeably easier than par for skilled players.
What Is Slope Rating?
Slope Rating evaluates how much harder the course plays for a bogey golfer (roughly a 20 to 24 handicap for men, 24 for women) compared to a scratch golfer. It measures the relative steepness of difficulty increase as a player's skill level drops.
- Standard Slope Rating: 113 (considered an average difficulty course for the target demographic).
- Minimum Slope: 55 (extremely flat, wide, and forgiving).
- Maximum Slope: 155 (extremely punitive with tight hazards, deep rough, and long carries).
How They Work Together in Your Handicap
When you log a score into our Handicap Tracker, both numbers are factored into the World Handicap System formula:
(Score - Course Rating) × (113 ÷ Slope Rating)
Without Slope Rating, a high-handicap player who shoots a 90 on a tight, heavily bunkered mountain course would receive the same differential credit as shooting a 90 on a flat, wide-open municipal course. Slope ensures fairness across all skill levels.
Seeing the Difference in Real Numbers
The cleanest way to understand what slope actually does is to hold the score constant and change only the course. Imagine the same golfer shooting 90 on three different layouts, each with a Course Rating of 71.0:
- Slope 105 (forgiving municipal): (90 − 71.0) × (113 ÷ 105) = 19 × 1.076 = 20.4
- Slope 113 (exactly average): (90 − 71.0) × (113 ÷ 113) = 19 × 1.000 = 19.0
- Slope 140 (severe championship test): (90 − 71.0) × (113 ÷ 140) = 19 × 0.807 = 15.3
Same golfer, same 90, same course rating — and a five-stroke spread in what the round was worth. The 90 on the 140-slope course was a far better performance, and the system records it that way. This is also why entering the wrong slope is not a rounding error; it is a systematic distortion applied to every round you log.
Who Assigns These Numbers, and How
Course and Slope Ratings are not set by the course owner or the head professional. They are assigned by trained rating teams working under a regional or state golf association, following the USGA Course Rating System. A team physically walks each set of tees and measures two categories of difficulty.
Effective playing length
This starts with measured yardage, then adjusts for factors that make the course play longer or shorter than the card says: elevation change, prevailing wind, roll on the fairways, dogleg geometry that forces a layup, and altitude.
Obstacle factors
Ten separate obstacle categories are scored hole by hole — topography, fairway width, green target size, recoverability and rough, bunkers, crossing and lateral water hazards, trees, green surface difficulty, and psychological pressure. Critically, each is evaluated twice: once for how it affects a scratch golfer and once for how it affects a bogey golfer.
That dual evaluation is where slope comes from. The rating team produces a Scratch Rating and a Bogey Rating, and slope is derived from the gap between them:
Slope Rating = (Bogey Rating − Course Rating) × 5.381 (men)
Slope Rating = (Bogey Rating − Course Rating) × 4.240 (women)
A wide, flat course with few forced carries barely punishes the weaker player more than the stronger one, so the gap is small and the slope is low. A course with water in front of every green, deep rough, and 200-yard carries off the tee devastates a bogey golfer while a scratch player navigates it, so the gap is large and the slope is high. Courses are re-rated roughly every ten years, or sooner after significant renovation.
Why a High Course Rating Doesn't Always Mean a High Slope
This is the distinction that catches most golfers out. The two numbers move independently, and all four combinations exist in the wild.
- High rating, low slope: a long, wide-open links course. Sheer length punishes everyone, but there is little trouble to find, so the bogey golfer is not disproportionately hurt.
- Low rating, high slope: a short, tight parkland course with water and trees everywhere. A scratch player can position their way around it comfortably; a bogey golfer loses three balls.
- High rating, high slope: a genuine championship test — long and penal. These are the hardest courses to score on at any level.
- Low rating, low slope: a short, forgiving resort or executive course. Everyone scores well.
When a friend tells you a course is "a 140 slope," they are telling you it will be brutal for mid and high handicaps specifically — not necessarily that a good player will struggle.
Which Numbers Should You Enter for Your Round?
Enter the Course Rating and Slope Rating for the exact set of tees you played, matching your gender's rating. Nothing else. This sounds obvious and is the most frequent data-entry error golfers make.
Most scorecards print a small grid with a row per tee colour and separate columns for men and women. Find your tee colour, find your column, and read across. If you moved up a set of tees partway through the round, or played a mixed set, the round is technically not acceptable for handicap purposes under strict WHS rules — though for a personal tracker most golfers just use the tees they played the majority of holes from and accept a small imprecision.
If the scorecard is missing the ratings entirely, which happens at some smaller municipal courses, check the course's website or your state golf association's course rating database before guessing. Guessing a slope of 113 when the real figure is 128 will understate every differential from that course by roughly 12%.
The My Courses page on this site exists precisely so you only have to look these numbers up once. Save the course with the correct rating and slope for your usual tees, and every future round auto-fills them correctly.
Frequently Asked Questions
Is a higher slope rating always harder?
Harder for a bogey golfer relative to a scratch golfer, yes. It does not automatically mean the course is hard in absolute terms — a short, tricky course can carry a high slope while still being scoreable for a low handicap.
Why is Course Rating a decimal but Slope a whole number?
Course Rating is expressed in strokes, and the rating system resolves to a tenth of a stroke. Slope is an index derived from a multiplication, deliberately scaled to a whole-number range of 55 to 155 with 113 at the centre.
Do these numbers change with weather?
No. Ratings are set for normal playing conditions. WHS handles unusual weather separately through the Playing Conditions Calculation, which adjusts differentials on days when scoring across an entire course was abnormally high or low.
My course has different ratings for the same tees. Why?
Almost always because you are looking at the men's and women's ratings side by side. They are calculated against different bogey-golfer benchmarks and are not interchangeable.