Golf Handicap Calculator

What is the Golf Handicap Calculator?

This tool calculates your Handicap Index using the official World Handicap System (WHS) formula adopted by the USGA and R&A — the same system used worldwide since 2020.

Step 1: Score Differential

Each round is first converted to a Score Differential, which adjusts your score for the specific course's difficulty: Score Differential = (113 ÷ Slope Rating) × (Adjusted Gross Score − Course Rating). The 113 is the Slope Rating of a course of "standard" difficulty, used as the reference point.

Step 2: Handicap Index

Your Handicap Index is the average of your best Score Differentials, multiplied by 0.96, then truncated (not rounded) to one decimal place. Exactly how many of your best differentials get used depends on how many rounds you have on record — with 20 rounds, it's your best 8; with fewer rounds, the official table below applies, with small downward adjustments for players with very few scores on record:

Fewer than 3 rounds isn't enough to calculate an official Handicap Index under WHS rules.

How to use it

1. Add each recent round: your Adjusted Gross Score, and that course's Course Rating and Slope Rating.
2. The Score Differential for each round calculates automatically.
3. Your Handicap Index updates automatically as you add rounds.

This calculator does not apply the Playing Conditions Calculation (a small weather/course-condition adjustment some clubs apply) or the soft/hard caps that limit how fast an index can rise — for an official, posted Handicap Index, use your national golf association's handicap system (GHIN in the US).