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Golf Handicap Calculator

World Handicap System Score Differential from score, course rating and slope, then your Handicap Index from the best of the last 20 rounds.

Golf Handicap Calculator: with the default inputs, handicap index is 16.3.

Try an example
This is the raw calculation. It does not apply the soft cap (Rule 5.8: increases beyond 3.0 strokes above your Low Handicap Index count at half rate), the hard cap (5.0 strokes above it), or the Playing Conditions Calculation, which your handicap system applies for you overnight. Your official Index is whatever your authorised handicap provider publishes.
Handicap Index
16.3

Portable across courses. Capped at 54.0.

This round's Score Differential
18.6
Scores in your record
20
Lowest differentials averaged
8
Average of those differentials
16.28
Rule 5.2a adjustment
0
Course Handicap
17
Playing Handicap
17
Net score this round
75
Assumptions
  • World Handicap System, Rules of Handicapping as verified against the R&A and USGA texts on 9 September 2026 (Rules 5.1a, 5.2a, 5.3, 6.1a, 6.2a).
  • All Score Differentials are treated as 18-hole differentials from acceptable scores; 9-hole rounds are combined into 18-hole differentials by your handicap provider, not here.
  • The soft cap and hard cap (Rule 5.8) and the Low Handicap Index (Rule 5.7) are not applied — both require a 365-day scoring history and at least 20 scores.
  • The Playing Conditions Calculation is offered as an input for illustration; in practice it is computed automatically overnight from the whole field's scores and is 0 on most days.
  • The score you enter is assumed already adjusted to net double bogey per Rule 3.1; this page does not cap holes for you.
  • Course Handicap is rounded to the nearest whole number for display. Rule 6.1a keeps the unrounded value for the Playing Handicap calculation, which this page also does.
Your record, oldest to newest — the shaded low 8 drive the Index
01020201612841Rounds ago (1 = most recent)
Score Differential
Rule 5.2a — how many scores count
Acceptable scores in your recordLowest differentials averagedAdjustmentYour Index under this row
31-212.9
41-113.9
51none14.9
62-114.2
7 to 82none15.2
9 to 113none15.4
12 to 144none15.6
15 to 165none15.7
17 to 186none15.9
197none16.1
208none16.3

The right-hand column applies each row's rule to the differentials you entered, so you can see how the Index tightens as a record fills up.

Math verified by automated testsUpdated 2026-09-093 sources cited

How this is worked out

The formula

Score Differential = (113 ÷ Slope Rating) × (adjusted gross score − Course Rating − PCC)
  rounded to the nearest tenth  (Rule 5.1a)

Handicap Index = average of the lowest N Score Differentials in your most recent 20,
                 plus the adjustment from the Rule 5.2a table, rounded to the nearest tenth
  20 scores → lowest 8, no adjustment
  19 → lowest 7 · 17–18 → lowest 6 · 15–16 → lowest 5 · 12–14 → lowest 4 · 9–11 → lowest 3
  7–8 → lowest 2 · 6 → lowest 2 − 1.0 · 5 → lowest 1 · 4 → lowest 1 − 1.0 · 3 → lowest 1 − 2.0
  Maximum Handicap Index: 54.0  (Rule 5.3)

Course Handicap = Handicap Index × (Slope Rating ÷ 113) + (Course Rating − par)   (Rule 6.1a)
Playing Handicap = unrounded Course Handicap × handicap allowance                  (Rule 6.2a)

Open How it’s calculated above to see this worked through with your own numbers.

What you enter

Adjusted gross score
Your score after capping each hole at net double bogey (par + 2 + any strokes you receive on that hole).from 30 to 200 · whole numbers only · defaults to 92
Course Rating
What a scratch golfer is expected to shoot from the tees you played. Printed on the scorecard, one decimal place.from 55 to 85 · defaults to 71.4
Slope Rating
Difficulty for a bogey golfer relative to a scratch golfer. 113 is the standard; the legal range is 55 to 155.from 55 to 155 · whole numbers only · defaults to 125
Par
Used only for the Course Handicap, which is now expressed relative to par.from 27 to 80 · whole numbers only · defaults to 72
Playing Conditions Calculation
Applied automatically overnight by your handicap system when the field as a whole scores unusually. You do not set it yourself.−1.0 — scoring was easier than expected · 0 — normal conditions (almost always) · +1.0 — harder than expected · +2.0 — much harder · +3.0 — extremely hard
Your recent Score Differentials
Most recent first. Only the last 20 count. Compute each one with the fields above, or copy them from your handicap record.up to 400 characters · defaults to "16.3, 18.1, 14.9, 20.2, 17.6, 15.4, 19.8, 22.1, 16.9, 18.7, 21.3, 17.2, 15.8, 19.1, 23.4, 16.1, 20.6, 18.3, 17.9, 21.7"
Include the round above in the list
Adds this round's differential as the newest score and drops the oldest if you already have 20.defaults to on
Handicap allowance(under More options)
100% for individual match play, 95% for individual stroke play, 85% for four-ball stroke play (Appendix C).a percentage · from 10 to 100 · defaults to 100

What you get back

Handicap Indexmain answer
Portable across courses. Capped at 54.0.
This round's Score Differential
Rounded to the nearest tenth, as Rule 5.1a requires.
Scores in your record
Lowest differentials averaged
Set by the Rule 5.2a table — 8 once you have 20 scores.
Average of those differentials
Rule 5.2a adjustment
A discount applied only when you have fewer than 5 scores, or exactly 6.
Course Handicap
Strokes you receive on this course from these tees, relative to par.
Playing Handicap
Course Handicap after the competition allowance.
Net score this round
Adjusted gross score minus your Course Handicap.

What this assumes

  • World Handicap System, Rules of Handicapping as verified against the R&A and USGA texts on 9 September 2026 (Rules 5.1a, 5.2a, 5.3, 6.1a, 6.2a).
  • All Score Differentials are treated as 18-hole differentials from acceptable scores; 9-hole rounds are combined into 18-hole differentials by your handicap provider, not here.
  • The soft cap and hard cap (Rule 5.8) and the Low Handicap Index (Rule 5.7) are not applied — both require a 365-day scoring history and at least 20 scores.
  • The Playing Conditions Calculation is offered as an input for illustration; in practice it is computed automatically overnight from the whole field's scores and is 0 on most days.
  • The score you enter is assumed already adjusted to net double bogey per Rule 3.1; this page does not cap holes for you.
  • Course Handicap is rounded to the nearest whole number for display. Rule 6.1a keeps the unrounded value for the Playing Handicap calculation, which this page also does.

About this calculator

The World Handicap System, live since 2020, replaced six separate national systems with one worldwide calculation. It answers a specific question: what do you shoot when you play well? Not your average — your potential. That is why it uses only your best rounds and ignores the rest.

Step one: the Score Differential

Every round becomes a Score Differential, which strips out how hard the course was so that rounds from different courses can be compared:

> 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 — a number like 71.4, not the par. Slope Rating measures how much harder the course plays for a bogey golfer than for a scratch golfer; 113 is the neutral standard, which is why it appears in the formula. A high slope means the course punishes weaker players, so a given score there earns a lower differential. The PCC is an overnight adjustment your handicap system makes when the whole field scores unusually high or low; you never set it yourself, and it is zero the overwhelming majority of the time.

The score you feed in is the adjusted gross score, capped hole by hole at net double bogey — par, plus two, plus any handicap strokes you get on that hole. One blow-up hole cannot wreck your handicap.

Step two: the Handicap Index

Take the lowest 8 of your most recent 20 differentials, average them, round to a tenth. That is your Index. With fewer than 20 scores, Rule 5.2a uses a smaller sample and, for very short records, subtracts a stroke or two to stop a single fluke round from setting an unrealistically low handicap. The full table is in the results, applied to the differentials you enter, so you can watch the Index settle as a record fills.

Step three: strokes on the day

Your Index is portable; the strokes you actually receive are not. Course Handicap = Index × (Slope ÷ 113) + (Course Rating − par), which is why a 14.0 index gets more strokes on a 140-slope course than on a 110-slope one, and why the figure is now expressed relative to par. In a competition the Course Handicap is then multiplied by an allowance — 95% for individual stroke play, 85% for four-ball, 100% for singles match play — to produce the Playing Handicap. Enter the allowance under More options.

What this page does not do

It does not apply the soft cap and hard cap (Rule 5.8), which slow down how fast an Index can rise: increases more than 3.0 strokes above your Low Handicap Index — the lowest Index in the last 365 days — count at half rate, and 5.0 strokes above it is an absolute ceiling. Both need a full year of scoring history. It also assumes every differential you enter came from an 18-hole round; nine-hole scores are combined into 18-hole differentials by your handicap provider. Your official Handicap Index is whatever your authorised handicap authority publishes — this page shows you the arithmetic behind it.

Frequently asked questions

How do you calculate a golf handicap?

Convert each round into a Score Differential — (113 ÷ Slope Rating) × (adjusted gross score − Course Rating) — then average the lowest 8 of your most recent 20 differentials and round to one decimal place. That average is your Handicap Index.

How many rounds do I need for a handicap?

Three 18-hole scores. With only three the system uses your single lowest differential and subtracts 2.0 strokes; with four it subtracts 1.0. The adjustments disappear at five scores and the sample grows until it reaches the lowest 8 of 20.

What is the difference between Handicap Index and Course Handicap?

Your Index is a portable number that describes your potential. Your Course Handicap converts it into strokes for a specific set of tees: Index × (Slope ÷ 113) + (Course Rating − par). A high-slope course gives you more strokes.

What is Slope Rating and why 113?

Slope measures how much harder a course plays for a bogey golfer than for a scratch golfer. 113 is the rating of a course of standard relative difficulty, so dividing by it normalises every course onto one scale. The legal range is 55 to 155.

What is the maximum golf handicap?

54.0 for both men and women under the World Handicap System (Rule 5.3). Individual committees may impose a lower limit for a particular competition.

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