Building the brackets: A deep dive on the NCAA tournament selection and seeding process

March Madness captivates basketball fans every year, but before the excitement of buzzer beaters and Cinderella stories comes a meticulous process that determines how teams are selected and seeded for the NCAA Division I Men's and Women's Basketball Championships.

Selecting Teams for March Madness

• Each committee member chooses the top eight teams, in no particular order, from teams that are under consideration.
• The top eight vote-getters are ranked 1 through 8 by each committee member, with the top four from that vote moving into the field. The other four are placed in a "holding room."
• The committee members then list eight more teams from the under-consideration list.
• The top four vote-getters join the other four in holding for a rank of those eight teams. The top four from that ranking are moved into the field.
• This process repeats itself until 37 at-large teams have been selected.

This ensures that only the best teams are selected, based on a variety of metrics and comprehensive evaluation. 

Learn more about each committees' selection criteria for the NCAA tournament.

Seeding Teams: Creating the True Seed List 

The NCAA Division I Men's and Women's Basketball Committees rank the 68 teams using a seed list, which orders teams from 1 through 68. This seed list remains unchanged once finalized and serves as the basis for placing teams into the tournament bracket. While the seed list is finalized Sunday morning, contingencies are put into place based on potential outcomes of Sunday's games. 

Teams are ranked and placed using a voting process:

• The seeding process begins with each committee member choosing the top eight teams, in no particular order, from teams that have already been voted into the field or have earned the automatic qualifier.
• The top eight vote-getters are ranked 1 through 8 by each committee member, with the top four from that vote moving into the top four spots on the overall seed list. The other four are placed in a "holding room."
• The committee members then list eight more teams from the teams that have already been voted into the field or have earned the automatic qualifier.
  The top four vote-getters join the other four in holding for a rank of those eight teams. The top four from that ranking are moved into the field as the initial 2 seeds (spots 5-8 on the overall seed list).
• This process repeats itself until all tournament teams have been seeded.
• Throughout selection week and right up until the morning of Selection Sunday, the committees will revisit the seed list, scrubbing it until they are satisfied with the order of the 68 teams. The scrubbing process involves comparing the first team with the second, the second with the third, the third with the fourth, and so on. When a team moves up a spot on the seed list, it is then compared with the next team up, and when a team moves down a spot on the seed list, it is compared with the next team down.

Key Men's Bracketing Principles

1. Regional assignments: The four No. 1 seeds are placed in separate regions, with the highest-seeded team choosing its preferred region.
2. Conference and rematch rules: The first four teams from the same conference are placed in different regions when they are among the top four seed lines. Teams from the same conference that have played three times during the season, including conference tournament games, cannot meet until the Elite Eight. Teams from the same conference that have met twice during the season, including the conference tournament, may not meet before the Sweet 16. If teams from the same league played just once during the season, they may meet as early as the second round. These principles can be relaxed if a league has nine or more teams in the tournament.
3. First Four games: The last four at-large teams on the committee's overall seed list, plus the last four teams on the overall seed list, make up the eight teams that compete in the First Four in Dayton, Ohio.
4. Geographical placement: Teams are placed as close to home as possible to maximize fan accessibility. Additionally, a team cannot play in a facility where it has played more than three games in a season or is the host school.
5. Bracketing adjustments: If necessary, a team may be moved up or down one seed line to meet bracketing principles. The committee balances regions across the top four seed lines (top 16 teams) using true seed numbers to ensure no region is significantly stronger than another. Ideally, there is never a difference of more than five between the region with the lowest total and the one with the highest.

Did you know? In men's basketball, because there are five conference championship games played on Selection Sunday, there are contingent seed lists based on those outcomes. Because bracketing can't begin until the overall seed list is finalized, there are several brackets produced Sunday, based on the combinations of Sunday's outcomes that impact the seed list.

Learn more about the March Madness selections process.

Key Women's Bracketing Principles

1. Regional assignments: The four No. 1 seeds are placed in separate regions, with the highest-seeded team choosing its closest regional location.
2. Conference and rematch rules: The first four teams from the same conference are placed in different regions. Teams from the same conference cannot meet until the regional final if they've played each other three or more times. If necessary, a team may be moved up or down one seed line to meet bracketing principles.
3. First Four games: The last four at-large teams, plus the lowest-seeded automatic qualifiers, play in First Four games at top 16 host sites.
4. Top 16 seeds hosting games: The top 16 seeded teams have the opportunity to host first- and second-round games at their home arenas if they meet hosting requirements.
5. Geographic and venue considerations: Teams are placed as close to home as possible to maximize fan accessibility. For regional competition, a team cannot play in an arena where it has played more than three games in a season.
6. Bracketing adjustments: If necessary, a team may be moved up or down one bracket line to meet bracketing principles. The committee balances regions using true seed numbers to ensure no region is significantly stronger than another.

Why Seeding Matters in March Madness

Seeding can have a significant impact on a team's tournament journey. Historically, No. 1 seeds have had the best chance of winning their respective tournament, but upsets are a big part of the March Madness drama.

Final Thoughts: Understanding the Madness Behind the Bracket

Understanding how teams are selected and seeded is critical for appreciating the complexity of March Madness. It's a careful balancing act that combines data-driven analysis with subjective judgment. The process may seem like a mystery to many, but by breaking down how seeding and selection works, fans can gain a greater appreciation for the tournament.

Stay Updated on March Madness:

• Men's tournament updates.
• Women's tournament updates.