Each week, the PGA Tour sets up its golf courses with the goal of identifying the world's best players while being fair, respecting the design and features of the host course(s) and creating a sense of drama for PGA Tour fans.
Some weeks, the golf courses are a little easier, meaning scores go lower and it takes more birdies and eagles to win. Some weeks, the golf course is a difficult test, and the Tour sets up the course to reflect its natural challenge.
Generally speaking, the PGA Tour's Rules and Competitions committee and agronomy staff set up the golf course with a standard guiding philosophy. As it relates to greens, the Tour wants them closely mown with some firmness and a reasonable speed accounting for the contours on the putting surfaces, as well the grass type, course conditions and expected weather.
That means the green speeds can vary from week to week on the PGA Tour, but they're not designed to vary but a tiny fraction from green to green.
Perhaps the slowest greens the players see all year is at Kapalua for the Tournament of Champions. The greens there are very exposed to the wind, meaning the Tour slows them down and has slightly higher grass heights to prevent balls from oscillating and rolling uncontrollably. The Stimpmeter readings on the Plantation Course are closer to 9 or 10.
Most weeks on the PGA Tour, however, the green speeds are in the range of a 12 on the Stimpmeter.
For the Masters, US Open, The Players and PGA Championship, the green speeds usually get anywhere from 13 to 14 on the Stimpmeter. Of course, that can change based on weather conditions, both forecast and unanticipated, but major championships often feature faster greens to place a greater emphasis on speed control and approach-shot accuracy.
The British Open Championship is an outlier compared to its major peers, primarily because its host rota features links courses susceptible to wind gusts, like at Kapalua. Green speeds are closer to a 10 on the Stimpmeter there.
As recently as a decade ago, green speeds were about a whole Stimpmeter point slower. However, championship-level golf has become increasingly obsessed with chasing green speeds as agronomy continues to improve, enabling setup crews to pursue faster greens.