The PGA Tour cut rule stipulates that, after 36 holes of most 72-hole tournaments, the top 65 players and ties qualify for the final two rounds and earn a paycheck for the week if they finish the golf tournament.
(There are several tournaments, including The American Express, which cut to the top 65 and ties after three rounds.)
During the weeks there is a cut, the PGA Tour purse is quoted based on exactly 65 players making the cut. Of course, that rarely happens. Most weeks, more than 65 players are getting through the cut and finishing the tournament. So, what does the PGA Tour do with paying prize money when more than 65 players make the cut?
Quite simply, the PGA Tour increases the purse.
For example, a purse on the PGA Tour is $20 million. The quoted purse covers the 18 percent cut for the winner, which is $3,600,000, all the way down to $43,000 for 65th place (if there's not a tie). In the event there are more than exactly 65 players who qualify for the weekend after the 36-hole cut, the purse is actually increased above and beyond the $20 million figure.
The PGA Tour pays out all players who make the cut, starting at 0.213 percent of the stated purse for 66th place and decreasing by increments of 0.002 percent all the way down to whatever number of players make the cut.
With the elimination of the secondary cut, or MDF Rule of 78, for the 2019-2020 PGA Tour season, every player who makes the 36-hole cut has a chance to move up the leaderboard for the final two rounds and improve their payday.
The same is true with FedEx Cup points. Every player who makes the cut and finishes the tournament earns FedEx Cup points. In standard events where the winner gets 500 FedEx Cup points, the 66th-place player earns 3.8 FedEx Cup points. The figure decreases by 0.1 points down to 85th place, when the points decrease from 1.5 to 1.45 for 86th place.