Your index, worked out the way the WHS does it.

Not an estimate, not "average your last five". The actual World Handicap System method: 113 over slope times score minus rating for every round, the best 8 of the last 20 (or the smaller-sample table with its adjustments when you have fewer), rounded to a tenth.

WHAT IT DOES

• Hole-by-hole entry with automatic net double bogey: each hole is capped at par + 2 + the strokes you get there from the stroke index, so the adjusted gross score is right without you doing it
• Course library: save each course and tee with its rating, slope, pars and stroke indexes; see the strokes you get on every hole for the tee you are about to play
• Exceptional score reduction: a round 7 or more below your index reduces every differential by 1 (10 or more: 2), as the rules require
• Low Handicap Index and caps: the lowest index in the last 365 days is tracked and the soft cap (half of any rise above +3) and hard cap (+5) are applied
• Score differential for every round from course rating and slope
• Handicap Index from the WHS table: 3 rounds to 20, with the -2, -1 and best-of adjustments applied correctly
• Counting rounds highlighted so you can see which scores are carrying you
• Course handicap for any tee: index × slope ÷ 113 + (rating − par)
• Playing handicap at your allowance (95% singles by default)
• What to shoot next: the differential you need to beat to lower your index, translated into a score on the tee you are playing
• Differential trend chart and a slump warning

Who it's for

Golfers without a club handicap who want a real one, society and league organizers doing handicaps for a group, and anyone who wants to see the maths behind the number the app gives them.

What you get

• The calculator (one .html file, runs in any browser, offline; works on a phone)
• A 2-page quick-start guide

PCC is not applied; for an official index, post scores with your association.

Good to know

• One file. No install, no account, no subscription, no internet needed after download.
• Your data stays on your computer. Export a backup any time; import it on another machine.
• Works on Mac, Windows, Linux and iPad (open the file in Safari or Chrome).
• Instant download.

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