How to calculate a golf handicap

Six steps, the exact formula, and a set of 20 real-looking rounds worked from start to finish.

Here's the whole thing on one page: the formula, the table, and a real set of 20 rounds worked through. If you just want the number, use the handicap calculator.

Step 1: Adjust each score

Add up your strokes, but no hole can count for more than net double bogey: par + 2 + the strokes you get on that hole. A 16 handicap gets a stroke on the 16 hardest holes, so their cap is par + 3. On the two easiest holes it's par + 2. New golfers without an index cap every hole at par + 5.

Step 2: Turn each score into a differential

Score differential = (113 ÷ slope rating) × (adjusted gross score − course rating − PCC)

Course rating is what a scratch golfer is expected to shoot from those tees. Slope says how much harder the course gets for everyone else. 113 is average. The PCC (playing conditions adjustment) is usually 0. Round each differential to one decimal.

Example: 92 from tees rated 70.9, slope 127: (113 ÷ 127) × (92 − 70.9) = 0.8898 × 21.1 = 18.8.

Step 3: Keep your 20 most recent

Only the last 20 differentials count. When you post a 21st, the oldest drops off. That keeps your handicap matched to how you play now.

Step 4: Average the best 8

Out of those 20, take the 8 lowest and average them. With fewer than 20 rounds:

Differentials on file	Which ones count	Adjustment
3	Lowest 1	−2.0
4	Lowest 1	−1.0
5	Lowest 1	0
6	Average of lowest 2	−1.0
7–8	Average of lowest 2	0
9–11	Average of lowest 3	0
12–14	Average of lowest 4	0
15–16	Average of lowest 5	0
17–18	Average of lowest 6	0
19	Average of lowest 7	0
20	Average of lowest 8	0

Step 5: Round it, and that's your index

Round to one decimal. The highest index you can have is 54.0.

Worked example: 20 rounds

A golfer who usually shoots around 90. The 8 counting rounds are highlighted.

Round	Score	Rating	Slope	Differential
1	92	70.9	127	18.8
2	88	71.4	131	14.3 ✓
3	95	72.1	134	19.3
4	90	69.8	122	18.7
5	86	70.2	125	14.3 ✓
6	91	71.0	129	17.5
7	97	72.6	138	20.0
8	89	70.5	124	16.9 ✓
9	93	71.8	132	18.1
10	87	69.9	121	16.0 ✓
11	94	72.0	133	18.7
12	90	70.9	127	17.0 ✓
13	99	73.1	140	20.9
14	88	70.2	125	16.1 ✓
15	85	69.6	119	14.6 ✓
16	92	71.4	131	17.8
17	96	72.3	136	19.7
18	90	70.5	124	17.8
19	89	71.0	129	15.8 ✓
20	91	70.8	126	18.1

The best 8 are 14.3, 14.3, 14.6, 15.8, 16.0, 16.1, 16.9, 17.0. They add up to 125.0, and divided by 8 that's 15.625. Rounded, the handicap index is 15.6.

So a golfer who averages about 91 carries a 15.6, not a 19 or 20. That's normal. A handicap shows your good days.

Step 6: Turn the index into strokes for today

Course handicap = handicap index × (slope ÷ 113) + (course rating − par)

At a course rated 72.4 with a slope of 135 and par 72, this golfer gets 15.6 × 135 ÷ 113 + 0.4 = 19.0, so 19 strokes. Work it out for any course with the course handicap calculator.

Caps and adjustments

Soft cap: if your index climbs more than 3.0 above your lowest index of the past 12 months, the climb past 3.0 is cut in half.
Hard cap: your index can't go more than 5.0 above that 12-month low.
Exceptional score: a differential 7.0 or more below your index takes an extra 1.0 off your index; 10.0 or more takes off 2.0.
Playing conditions: on days when scores at a course come in far off normal, every differential that day moves by −1 to +3.

More handicap tools

Course handicap calculatorHow many strokes you get on a given course and tee.Score differential calculatorTurn one round into the number your index is built from.Course rating and slopeWhat the two numbers mean, plus a lookup for 10,000+ courses.Playing handicapAllowances for scrambles, four-ball, match play and more.Net double bogeyThe most you can post on each hole, worked out for your course.9-hole handicapCourse handicap for 9 holes and how 9-hole rounds count.

Common questions

What is the formula for a golf handicap?

Handicap index = the average of your lowest 8 score differentials out of your last 20. Each differential = (113 ÷ slope) × (adjusted score − course rating − PCC).

Do I use my real score or my adjusted score?

Your adjusted score: every hole capped at net double bogey. Otherwise one disaster hole would push your handicap up.

Can I calculate a handicap with fewer than 20 rounds?

Yes. Starting at 3 rounds the index uses fewer differentials, and with 3 to 6 rounds an extra adjustment is taken off. See the table above.

Why is my handicap lower than my average score minus par?

Because it uses your best 8 rounds, not all 20. Most golfers average about 3 shots worse than their course handicap.

What does 113 mean in the handicap formula?

It is the slope rating of a course of standard difficulty. Dividing by 113 scales your score up on easy courses and down on hard ones, so rounds from different courses can be compared.

Updated November 2026