Sources & Assumptions
GolfVectorLab's rule-based calculations are built from the following primary references, last reviewed 2026-09-13. Rule profiles are reviewed on this schedule and whenever the governing body publishes a material update, not on a fixed content calendar.
Primary references
- United States Golf Association, World Handicap System updates and rules of handicapping: usga.org, World Handicap System revisions
- The R&A, Course Handicap Calculator and World Handicap System guidance: randa.org, Course Handicap Calculator
- National Golf Foundation, U.S. golf participation research, used for market and product context rather than any single engine's formula: ngf.org, golf industry research
- The R&A, global golf participation research, used for the same context purpose: randa.org, global participation research
Standing assumptions
Where an engine relies on an assumption rather than a value you supplied, that assumption is stated next to the result, not buried in a separate page. The assumptions below apply across the site unless a specific engine states otherwise:
- Bag and distance reasoning uses the player's own reported carry data. It does not substitute a manufacturer's stated average distance for an individual player's actual performance.
- Handicap and scoring engines assume the United States rule profile of the World Handicap System unless a future rule-profile module states otherwise. International rule variations are out of scope until a dedicated module is built and locked.
- Condition-adjustment estimates are scoped for practice and casual-round planning. They are not a substitute for real-time, on-course judgment or official tournament conditions.
- Any result labeled as an estimate carries a stated confidence level and, where the underlying sample is small, a range rather than a single value.
What is explicitly out of scope
GolfVectorLab does not maintain a live feed of course data, tee sheets, weather, or retail pricing, and does not claim any of its bag or equipment reasoning as a substitute for a professional club fitting. See the disclaimer and responsible-use page for the complete list of boundaries.