Golf
Ball Sports · 7 specs
Direct Answer
Conforming golf balls are regulated by the USGA and The R&A under the Rules of Golf Appendix III. A conforming golf ball must have a minimum diameter of 1.680 in (42.67 mm), a maximum weight of 1.620 oz (45.93 g), spherical symmetry, and an initial velocity not exceeding 250 ft/s (76.2 m/s) at 75 °F under standard test conditions.
Source: USGA (United States Golf Association) / The R&A Equipment Rules · Last reviewed Aug 28, 2026
Specs
| Minimum Diameter | 42.67 mm (1.680 in) minimum size |
| Maximum Mass / Weight | 45.93 g (1.620 oz) maximum weight |
| Maximum Initial Velocity | 76.2 m/s (250 ft/s ±2% tolerance at 75 °F) |
| Overall Distance Standard (ODS) | 317.0 yards (max distance cap on mechanical launcher) |
| Standard Dimple Count | 300–450 Symmetrical circular dimples (avg. 336–392) |
| Average Dimple Depth | 0.25 mm (0.010 in) |
| Standard Layer Construction | 2-Piece, 3-Piece, 4-Piece, or 5-Piece Polybutadiene core with Urethane / Surlyn cover |
Dimple Aerodynamics & Layer Architectures
- Dimple Boundary-Layer Physics: Smooth golf balls travel less than half the distance of dimpled balls. The 300–450 dimples trip the laminar airflow into a turbulent boundary layer, delaying flow separation, reducing low-pressure drag behind the ball, and generating aerodynamic Magnus lift.
- Multi-Layer Construction: 2-Piece balls combine a large polybutadiene rubber core with a durable Surlyn cover for maximum distance and low spin. Tour-grade 3-piece, 4-piece, and 5-piece balls incorporate thin elastomeric mantle layers and cast urethane covers to maximize greenside backspin while controlling driver launch.