How Browser-Based Golf Tracking Works — And the Math Behind Your Handicap
Most handicap services are built the same way: you create an account, your scores are uploaded to a company's database, and you pay a yearly fee for the privilege of reading your own numbers back. MyGolfTrackers is built the opposite way. There is no account, no server, and no fee, because your rounds are never transmitted anywhere. Everything you enter is written to local storage — a small, permanent storage area that every modern web browser sets aside for individual websites, right on the device you are holding.
When you save a course or log a round, the site converts that entry into a compact block of text and hands it to your browser to keep. It stays there after you close the tab, after you lock your phone, and after you turn the phone off. The next time you open the site, the page reads that block back and rebuilds your history. Because the data is scoped to this one domain, no other website can read it, and because it never leaves the handset, there is no database anywhere holding your scores. The honest tradeoff is portability: your rounds live on one device only. Switching phones, clearing your browsing data, or playing in private browsing mode will lose them. For a personal tracker most golfers keep on a single phone, that is usually a fair trade for total privacy and a zero-dollar price tag.
The Score Differential — the number that makes rounds comparable
The handicap math itself is the standard World Handicap System calculation, and it is far less mysterious than it looks. Shooting 88 on a short municipal track is not the same achievement as shooting 88 on a long championship layout, so a raw score cannot be compared across courses. The WHS solves that by converting every round into a Score Differential using two numbers printed on the scorecard at every course — the Course Rating (what a scratch golfer is expected to shoot) and the Slope Rating (how much harder the course plays for a bogey golfer):
Score Differential = (Gross Score − Course Rating) × (113 ÷ Slope Rating)
The 113 is not arbitrary — it is the Slope Rating of a course of average difficulty, which makes it the yardstick everything else is measured against. Dividing 113 by the actual slope produces a scaling factor that stretches or compresses your score depending on how punishing the course is. An 88 at a course rated 71.4 with a slope of 128 becomes (88 − 71.4) × (113 ÷ 128), or 14.7. That same 88 on an easier course would produce a higher differential, because you were given less help by the layout.
Your Handicap Index is then built from those differentials rather than from your scores. The tracker keeps your most recent 20 rounds and averages only the lowest ones — a sliding scale that starts at your single best differential when you have just three rounds logged and widens to your best eight once you reach twenty. That deliberate bias toward your better days is why a handicap represents your potential scoring ability, not your average round. Three rounds is the minimum before any index appears at all.
If you want the full walkthrough, the WHS handicap formula guide breaks down every step of the calculation, and Course Rating vs. Slope Rating explains where those two scorecard numbers come from.