RULES
ESPN's bracketology efforts are focused on predicting the NCAA tournament field, just as we expect the NCAA Division I basketball committee to select the field in March. In his on-field projections, ESPN bracketologist Charlie Creme uses the same data the committee prefers, including the strength of the schedule and other season metrics, including NET and team standings data similar to what is available from the NCAA. Visit the NCAA website for a more complete understanding. NCAA selection criteria.
64-team grid
The 64-team bracket is the standard version of the NCAA tournament field, in place since 1994. However, if the field is 64 teams in 2021, there will be some key differences from past years.
The main difference from a normal year is, of course, the entire NCAA Tournament being held in one location. This eliminates the need for geographic considerations when planting. There will also be at least one fewer automatic qualifier this season, as the Ivy League's decision to opt out of the 2020-21 season will reduce the number of AQ participants to 31 this season.
48-team bracket
In this projection, the shortened selection process would reduce the number of teams by eight overall and eight automatic qualifiers (the latter of which would still receive a unit of revenue). The top four seeds in each region will advance to the second round, with four first round games per region – 5 vs. 12, 6 vs. 11, 7 vs. 10 and 8 vs. 9.
Bracket of 16 teams
In this projection, the committee selects and seed the top 16 available teams. There are no automatic qualifications, although all non-participating conference champions receive an assigned revenue unit.
To maintain some sense of national balance, the conference is limited to four teams. And no region can have more than one team from the same conference.
