What is March Madness: The NCAA tournament explained

March Madness is one of the most anticipated and watched events in all of sports. Here’s everything you need to know about the NCAA Division I men's basketball tournament, which has been played since 1939.

What is March Madness?

The NCAA Division I men’s basketball tournament is a single-elimination tournament of 68 teams that compete in seven rounds for the national championship. The penultimate round is known as the Final Four, when (you guessed it) only four teams are left.

What (and when) is Selection Sunday?

Selection Sunday is the day when the Selection Committee reveals the full NCAA tournament bracket, including all teams and all seeds. We update this article every year with information on when Selection Sunday is and how to watch the bracket reveal.

When is this year's March Madness men's tournament?

Here is the full schedule for this season's 2024 NCAA men's basketball tournament.

• Selection Sunday: Sunday, March 17
• First Four: March 19-20
• First round: March 21-22
• Second round: March 23-24 
• Sweet 16: March 28-29 
• Elite Eight: March 30-31 
• Final Four: Saturday, April 6 at State Farm Stadium in Glendale, Arizona
• NCAA championship game: Monday, April 8 at State Farm Stadium in Glendale, Arizona

Here was the game-by-game schedule for the 2023 men's tournament:

Where can I get an NCAA bracket?

You can click or tap here to get a printable .PDF of the NCAA bracket. It will open in a new tab or window. You can also go here to see the official interactive bracket.

When did March Madness start?

The first NCAA Division I men’s basketball tournament was in 1939 and was held every year until the 2019-20 season. The event was canceled in 2020 because of the coronavirus pandemic.

How has the tournament changed since 1939?

The inaugural tournament had just eight teams, and saw Oregon beat Ohio State 46-33 for the title:

In 1951, the field doubled to 16, and kept expanding over the next few decades until 1985, when the modern format of a 64-team tournament began. In 2001, after the Mountain West Conference joined Division I and received an automatic bid, pushing the total teams to 65, a single game was added prior to the first round. In 2011, three more teams were added, and with them, three more games to round out the First Four.

Where did the term “March Madness” come from?

March Madness was first used to refer to basketball by an Illinois high school official, Henry V. Porter, in 1939, but the term didn’t find its way to the NCAA tournament until CBS broadcaster Brent Musburger (who used to be a sportswriter in Chicago) used it during coverage of the 1982 tournament. The term has been synonymous with the NCAA Division I men’s basketball tournament ever since.

How are the teams selected?

There are two ways that a team can earn a bid to the NCAA tournament. The 32 Division I conferences all receive an automatic bid, which they each award to the team that wins the postseason conference tournament. Regardless of how a team performed during the regular season, if they are eligible for postseason play and win their conference tournament, they receive a bid to the NCAA tournament. These teams are known as automatic qualifiers.

The second avenue for an invitation is an at-large bid. The selection committee (more on them in a second) convenes on Selection Sunday, after all regular season and conference tournament games are played, and decides which 36 teams that are not automatic qualifiers have the pedigree to earn an invitation to the tournament.

What is the March Madness selection committee?

The NCAA Men's Division I Basketball Committee is responsible for selecting, seeding and bracketing the field for the NCAA tournament. School and conference administrators are nominated by their conference, serve five-year terms and represent a cross-section of the Division I membership.

How do they decide which teams get an at-large bid?

There are a multitude of stats and rankings that the Selection Committee takes into account, but there is no set formula that determines whether a team receives an at-large bid or not.

What happens once the teams are selected?

Once the field of 68 is finalized, each team is assigned a seed and placed in one of four regions, which determines their first round matchups and their path to the championship.

What are seeds?

The NCAA men’s basketball tournament is made up of 68 teams. On Selection Sunday, before any tournament game is played, those teams are ranked 1 through 68 by the Selection Committee, with the best team in college basketball — based on regular season and conference tournament performance — sitting at No. 1. Four of those teams are eliminated in the opening round of the tournament (known as the First Four), leaving us with a field of 64 for the first round.

Those 64 teams are split into four regions of 16 teams each, with each team being ranked 1 through 16. That ranking is the team’s seed. 

In order to reward better teams, first-round matchups are determined by pitting the top team in the region against the bottom team (No. 1 vs. No. 16). Then the next highest vs. the next lowest (No. 2 vs. No. 15), and so on. In theory, this means that the 1 seeds have the easiest opening matchup in the bracket.

How to watch March Madness:

Every March Madness game will be broadcast on either TBS, TNT, TruTV or CBS. You can also stream every game on March Madness Live. 

How can you participate in March Madness?

By filling out a bracket! The Bracket Challenge Game, the official bracket game of the NCAA, will open immediately after the committee announces the field on Selection Sunday. The brackets will lock before the first game of the first round begins, so get your picks in before then. How hard is filling out a bracket? Well no one has ever gotten a perfect bracket, but that shouldn’t stop you from trying.

What are the odds of a perfect bracket?

• About 1 in 9,223,372,036,854,775,808 (if you just guess or flip a coin)
• Roughly 1 in 120.2 billion (if you know a little something about basketball, like not picking all 16 seeds to make the Final Four)

You can see how we arrived at those numbers in this article, first written in 2018 by NCAA.com's Daniel Wilco.

Who has won every NCAA tournament?

Since the tournament’s inception, no team has won more than UCLA, which has 11, 10 of which came a span of 12 years from 1964 to 1975.

Here is the list of every men’s basketball national championship since the NCAA tournament first started in 1939:

*Louisville’s participation in the 2013 tournament was later vacated by the Committee on Infractions.

March Madness glossary:

The Madness of March isn’t just confined to what happens on the basketball court. When discussing teams, there are a bevy of statistics, terms, and acronyms thrown out. There’s a team’s NET rankings, KPI, and BPI. The SOS and the SOR. The automatic bid and the at-large bid. It can be a bit daunting.

Maybe you’ve never heard of any of these, maybe you just need a quick refresher. Either way, we’ve compiled a list of the 29 most helpful terms when dealing with the NCAA tournament. These are stats and phrases that the Selection Committee will use to determine the field, and understanding what they mean can go a long way in helping you make informed decisions while filling out your bracket.

At-large bid — Teams that receive a bid to the NCAA tournament are broken into two categories: At-large bids, and automatic bids. The selection committee hands out 36 at-large bids to teams that did not win their conference tournament, but impressed the committee enough to earn a trip to the tournament. There is no limit on the number of at-large teams the committee may select from one conference.

Automatic bid — In Division I, there are 32 conferences. Each has its own conference tournament at the conclusion of the regular season. Teams that win this tournament, regardless of their regular-season performance, automatically earn a trip to the NCAA tournament. 

AP ranking – The Associated Press has been ranking the top basketball teams since 1948. In its current form, the poll ranks the top 25 teams in Division I via a ranking that is compiled from the ballots of 65 sports journalists across the country. The ranking has no official weight in the selection process, and even a No. 1 ranking in the AP poll does not technically guarantee a team a bid to the NCAA tournament. View the current AP rankings here.

BPI — College Basketball’s Power Index, invented by ESPN, is a statistic that measures how far above or below average every team is, and projects how well the team will do going forward. The index uses two measurements to do this: BPI Offense (measure of a team’s offensive strength compared to an average offense) and BPI Defense (measure of a team’s defensive strength compared to an average defense). BPI is calculated by finding the difference between these two measurements. View the current BPI rankings here.

The bubble — A team that is “on the bubble” for the NCAA tournament is one whose qualification for the tournament could go either way. They’re on the verge of making the field of 68, but an invitation isn’t guaranteed.

Cinderella — Much like the titular character from the fairy tale, a Cinderella team is one that is much more successful than expected. Examples in March would be Villanova’s 1985 championship run, when the eighth-seeded Wildcats became the lowest seeded team to ever win the title, knocking off the heavy favorite Georgetown.

Defensive efficiency — A simple statistic that calculates the points allowed per 100 defensive possessions. For example, if Team A’s opponent scored 80 points in a game with 75 possessions, Team A’s defensive efficiency would be 106.7. View current defensive efficiency rankings here.

Elite Eight — The fourth round of the tournament, when just eight teams remain, is known as the Elite Eight. This round is the final game for each regional, before the four winners move on to the national semifinal, known as the Final Four.

Final Four — The fifth round of the tournament, when just four teams remain, is known as the Final Four. This is the penultimate round of the tournament, when the winners of each regional face off for a chance to play in the championship game.

First Four — When the NCAA tournament was expanded to 68 teams, a new round was added to the format: The First Four. Four games, played on the Tuesday and Wednesday after Selection Sunday determine which of eight teams advance to the first round of the tournament.

First four out — When ranking all 68 teams in the NCAA tournament, the First Four Out fall in spots 69-72. These teams will not make the NCAA tournament, but will be the top-seeded teams in the NIT Championship.

KPI — KPI Sports ranks every team’s wins and losses on a scale of -1.0 (the worst possible loss) to +1.0 (the best possible win), and averages these scores across a season to give a score to a team’s winning percentage. The formula uses opponent’s winning percentage, opponent’s strength of schedule, scoring margin, pace of game, location, and opponent’s KPI ranking. View the current KPI rankings here.

Last four in — Another unofficial term, the "last four in" refers to the final four teams that receive at-large bids to the tournament. These are teams that are usually on the bubble as Selection Sunday draws near.  

NET — NCAA Evaluation Tool was a new ranking in 2018-19 that relies on game results, strength of schedule, game location, scoring margin, net offensive and defensive efficiency, and the quality of wins and losses. The ranking replaces RPI as the main sorting tool for the selection committee. Some of the unique aspects of the NET include the omission of game date and order (to give equal importance to both early and late-season games), and the inclusion of a cap of 10 points for winning margin (to prevent teams needlessly running up the score in a game where the outcome was certain).

Offensive efficiency — Points scored per 100 offensive possessions. For example, if a team scored 95 points in a game with 85 possessions, their offensive efficiency would be 115.9. View current offensive efficiency rankings here.

Pace/Tempo — An estimate of the number of possessions a team has per regulation (40 minutes). 

Per-40 stats — A reference used to compare two or more players who do not play the same amount of minutes per game. It is measured by taking each statistic, dividing it by the minutes played per game, and then multiplying it by 40 — a full regulation game. For example, if Player A scores an average of 20 points in 30 minutes of play, his points per-40 would be 26.7.

POM — Kenpom.com, run by Ken Pomeroy, is a website devoted to advanced basketball statistics. The site gives an overall rating to each Division I team throughout the season based on a multitude of advanced metrics. The Selection Committee uses these rankings to help evaluate teams. 

Quadrants (Q1, Q2, Q3, Q4) — In order to determine the strength of a team’s wins or losses, the selection committee divides the team’s record into four quadrants on each team sheet. The quadrants are meant to serve as an indicator of how good a team’s wins are, or how bad their losses are. Each quadrant is divided based on a combination of the location of the game — Home (H), Neutral court (N), or Away (A) — and the opponent’s NET ranking.

• Q1: H: 1-30; N: 1-50; A: 1-75
• Q2: H: 31-75; N: 51-100; A: 76-135
• Q3: H: 76-160; N: 101-200; A: 136-240
• Q4: H:161-353; N: 201-353; A: 241-353

Regional — The NCAA tournament bracket is split into four regionals. The South, East, West, and Midwest. The first four rounds of the tournament are played in regionals, with the Elite Eight serving as the regional championship game. Teams are assigned a regional based on a combination of factors, such as overall seed, proximity to the regional, the other teams in that regional, and more.

SAG — On a team sheet, “SAG” stands for Sagarin rankings, from sagarin.com. The Sagarin rankings account for score differentials, strength of schedule, and weights for how recent a game was (wins in February are worth more than wins in November). Sagarin rankings differ from KenPom rankings in that efficiency is not taken into account. View the current rankings here.

Seed — 68 teams earn bids to the NCAA tournament, and each one receives a seed — from 1 to 16 —that determines where the team will be placed in the bracket. After the First Four, there are four of every seed. The seeds are also ranked overall from 1 to 68. This overall ranking affects the order in which team locations are selected (with higher-ranked teams getting preference), and which teams play in the First Four (the four lowest-seeded at-large teams and the four lowest-seeded automatic qualifiers go to the First Four).

Selection committee —The 10-member NCAA Men's Division I Basketball Committee is responsible for selecting, seeding and bracketing the field for the NCAA Tournament. School and conference administrators are nominated by their conference, serve five-year terms and represent a cross-section of the Division I membership.

Selection Sunday — The day everyone waits for, when the Selection Committee announces the tournament field. This year, Selection Sunday is March 17.

Strength of record — From ESPN: “Strength of Record (SOR) is a measure of team accomplishment based on how difficult a team's W-L record is to achieve. SOR reflects the chance a typical 25th ranked team would have team's record or better, given the schedule on a 0 to 100 scale, where 100 is best.”

Strength of schedule — Strength of Schedule (or SoS) measures the difficulty of a team’s schedule, based on the win percentage of the team’s opponents.

Sweet 16 — The third round of the tournament, where only 16 teams remain. The winner of each game will play in the Elite Eight.

Team sheet — A one-page document for every team in Division I that helps the committee get a complete picture of that team’s performance during the season. The team sheets contain in-depth team information about strength of schedule, performance against top-50 teams and home/road records.