Cooper Flagg was born on December 21, 2006. As of April 2026, during the latter stages of the 2025-26 NBA regular season, he is 19 years old. Having been selected as the first overall pick in the 2025 NBA Draft by the Dallas Mavericks, Flagg entered the professional ranks as one of the youngest featured starters in the league.

Exact Age and Birth Date Information

The official birth date of Cooper Flagg is December 21, 2006. This birth date placed him in a unique position within the basketball recruiting and professional eligibility cycles. Born in Newport, Maine, Flagg's age has been a central point of discussion due to his early physical development and his strategic decision to reclassify during his high school years.

To understand his current status as a 19-year-old in the NBA, it is necessary to look at the chronological milestones he reached prior to his 20th birthday:

  • Age 15: Named the Maine Gatorade Player of the Year as a freshman at Nokomis Regional High School.
  • Age 16: Transferred to Montverde Academy and excelled in the Nike EYBL circuit.
  • Age 17: Committed to Duke University after reclassifying from the high school class of 2025 to 2024.
  • Age 18: Drafted 1st overall in the 2025 NBA Draft on June 26, 2025.
  • Age 19: Reached on December 21, 2025, during his rookie season with the Dallas Mavericks.

The Impact of Reclassification on Career Timing

A significant factor in Flagg's professional timeline was his decision in August 2023 to reclassify. Originally a member of the class of 2025, Flagg moved up to the class of 2024. This move was technically feasible because his birth year (2006) allowed him to meet the age requirements for the 2025 NBA Draft.

According to NBA eligibility rules, a player must be at least 19 years old during the calendar year of the draft and at least one NBA season must have elapsed since the player's graduation from high school. By graduating in the spring of 2024 at age 17 and turning 18 in late 2024, Flagg was eligible to enter the NBA in the summer of 2025, where he would turn 19 during his first professional season.

Collegiate Age Milestones at Duke University (2024-2025)

During the 2024-25 NCAA season, Flagg played for the Duke Blue Devils as an 18-year-old freshman. His statistical output was record-breaking for a player of his age group. In 37 appearances, all of which were starts, he averaged 19.2 points, 7.5 rebounds, 4.2 assists, 1.4 steals, and 1.4 blocks per game.

Scoring Records as an 18-Year-Old

On January 11, 2025, at the age of 18 years and 21 days, Flagg set a new freshman scoring record for both Duke University and the Atlantic Coast Conference (ACC). In a game against Notre Dame, he recorded:

  • Points: 42
  • Field Goals: 11-of-14
  • Three-Pointers: 4-of-6
  • Free Throws: 16-of-17
  • Other Stats: 6 rebounds, 7 assists

This performance contributed to his selection as the Consensus National Player of the Year, making him only the second freshman in history, alongside Zion Williamson, to receive the honor at Duke.

2025 NBA Draft and Professional Entry

Cooper Flagg was selected with the 1st overall pick in the 2025 NBA Draft by the Dallas Mavericks on June 26, 2025. At the time of his selection, he was 18 years and 187 days old. He joined Mark Aguirre as the only players in Dallas Mavericks history to be selected at the top of the NBA draft.

Upon signing his rookie contract on July 2, 2025, Flagg became the focal point of the Mavericks' roster overhaul. His youth and physical profile—listed at 6'9" and 205 lbs—allowed the team to integrate him into a high-usage role immediately.

Statistical Breakdown of the 2025-26 NBA Rookie Season

The 2025-26 season served as Flagg's introduction to professional basketball. His performance across different months provides a clear view of his adaptation to the NBA pace while still being 18 and later 19 years old.

November 2025: Initial Professional Integration

During November 2025, while still 18 years old, Flagg displayed high-level consistency. His statistics from mid-November include:

  • Nov 10 vs. Milwaukee: 26 points, 9 rebounds, 4 assists, 2 steals in 35 minutes.
  • Nov 12 vs. Phoenix: 16 points, 6 rebounds, 6 assists, 3 steals, 2 blocks.
  • Nov 14 vs. LA Clippers: 16 points, 5 rebounds, 1 steal in 48 minutes (overtime).
  • Nov 16 vs. Portland: 21 points, 8 rebounds, 5 assists, 2 blocks in 37 minutes.
  • Nov 17 vs. Minnesota: 15 points, 1 rebound, 2 assists in 27 minutes.

At this stage, his season averages hovered around 15.5 PPG and 6.3 RPG.

January 2026: Establishing Elite Status

By January 2026, having recently turned 19, Flagg's scoring output increased significantly.

  • Jan 19 vs. New York: 18 points, 7 rebounds, 3 assists in 28 minutes.
  • Jan 22 vs. Golden State: 21 points, 11 rebounds, 2 assists in 30 minutes.
  • Jan 24 vs. LA Lakers: 16 points, 7 rebounds, 6 assists in 34 minutes.
  • Jan 29 vs. Charlotte: 49 points, 10 rebounds, 3 assists, 1 block in 38 minutes.
  • Jan 31 vs. Houston: 34 points, 12 rebounds, 5 assists, 1 block in 39 minutes.

His 49-point performance on January 29 was noted as one of the highest scoring games by a 19-year-old rookie in NBA history, shooting 20-of-29 from the field.

March 2026: Versatility and Playmaking

In late March, Flagg continued to fill the stat sheet across multiple categories:

  • Mar 23 vs. Golden State: 32 points, 9 assists.
  • Mar 25 vs. Denver: 26 points, 8 rebounds, 7 assists, 1 block, 2 steals.
  • Mar 27 vs. Portland: 24 points, 3 rebounds, 2 assists, 4 steals.
  • Mar 30 vs. Minnesota: 12 points, 4 rebounds, 1 assist, 2 blocks.
  • Mar 31 vs. Milwaukee: 19 points, 10 rebounds, 3 assists, 1 block, 3 steals.

April 2026: Late Season Peak

The final month of the 2025-26 regular season saw Flagg reach a career-high in single-game scoring.

  • Apr 3 vs. Orlando: 51 points, 6 rebounds, 3 assists, 3 steals, 1 block. He shot 19-of-30 from the field and 6-of-9 from three-point range.
  • Apr 5 vs. LA Lakers: 45 points, 8 rebounds, 9 assists, 2 steals, 1 block.
  • Apr 7 vs. LA Clippers: 25 points, 9 rebounds, 2 assists, 1 block.
  • Apr 8 vs. Phoenix: 11 points, 11 rebounds, 6 assists, 1 steal, 1 block.
  • Apr 10 vs. San Antonio: 33 points, 6 rebounds, 5 assists.
  • Apr 12 vs. Chicago: 10 points, 4 rebounds in 10 minutes (limited due to injury).

By April 25, 2026, his season statistics stabilized at approximately 21.0 PPG, 6.7 RPG, and 4.5 APG.

Physical Profile and Technical Attributes at Age 19

The physical dimensions of Cooper Flagg have remained consistent since his entry into the NBA. He is officially measured at 6 feet 9 inches (2.06 meters) with a weight of 205 pounds (93 kg).

His technical profile at age 19 includes:

  1. Versatile Defending: Capable of guarding multiple positions due to his lateral quickness and 6'9" frame.
  2. High-Level Playmaking: Averaging over 4 assists per game as a forward, demonstrating advanced court vision for his age.
  3. Shooting Efficiency: Maintaining a field goal percentage above 50% in numerous high-volume scoring games.
  4. Shot Blocking: Utilizing his length to record averages above 1 block per game throughout his freshman college year and rookie professional season.

Comparative Age Milestones in NBA History

Comparing Flagg's age to other historical figures provides context for his 2025-26 season.

Player Draft Age Rookie Season Age PPG (Rookie)
Cooper Flagg 18 years, 6 months 18/19 years ~21.0
LeBron James 18 years, 6 months 18/19 years 20.9
Kevin Durant 18 years, 9 months 19 years 20.3
Zion Williamson 18 years, 11 months 19 years 22.5

Flagg's 51-point game at age 19 places him in an exclusive category of teenagers who have scored 50 or more points in a single NBA game.

NBA Eligibility and Age Regulations

The current NBA Collective Bargaining Agreement (CBA) mandates specific age requirements that directly impacted Flagg’s timeline. To be eligible for the 2025 NBA Draft, Flagg had to ensure:

  • The 19-Year Rule: He must turn 19 during the 2025 calendar year. (Born Dec 2006, he turned 19 in Dec 2025).
  • The "One Year Out" Rule: He must be at least one year removed from his high school graduation. (Graduated 2024, drafted 2025).

These rules prevented him from entering the league directly at age 17 or 18 without the requisite year of collegiate or alternative professional play.

Frequently Asked Questions Regarding Cooper Flagg's Age

How old was Cooper Flagg when he was drafted?

Cooper Flagg was 18 years old when he was selected as the No. 1 overall pick on June 26, 2025. He celebrated his 19th birthday later that year on December 21.

When does Cooper Flagg turn 20?

Cooper Flagg will turn 20 years old on December 21, 2026. This will occur during his second season in the NBA.

What is Cooper Flagg's birth date?

His birth date is December 21, 2006.

How did reclassification affect his age at the professional level?

Reclassification allowed Flagg to complete high school in 2024 instead of 2025. This made him eligible for the 2025 NBA Draft a full year earlier than his original peer group. Consequently, he entered the NBA at 18 instead of 19.

Is Cooper Flagg the youngest player in the NBA?

While specific rosters vary by season, Flagg was among the youngest players in the league during the 2025-26 season, as he did not turn 19 until nearly two months into the regular season.

Summary of Age and Career Status

Cooper Flagg, born December 21, 2006, is currently 19 years old as of April 2026. His trajectory from a 15-year-old high school standout in Maine to the 18-year-old top pick in the 2025 NBA Draft highlights a highly accelerated professional timeline. As a member of the Dallas Mavericks, his rookie season has been defined by statistical milestones that rival the production of previous elite prospects at the same age. With his 20th birthday approaching in late 2026, Flagg remains one of the youngest high-usage players in professional basketball.