Brock Richard Purdy (born December 27, 1999) is an American professional football quarterback for the San Francisco 49ers of the National Football League (NFL). He played college football for the Iowa State Cyclones and was selected by the 49ers with the final pick in the 2022 NFL draft, becoming that year's Mr. Irrelevant.

Purdy began his rookie season in the NFL as the third-string quarterback but took the starting role following injuries to Trey Lance and Jimmy Garoppolo. Winning all five regular-season games that he started, Purdy played a key role in the 49ers' ten-game winning streak, securing a division title and an NFC Championship Game appearance. Purdy continued as the 49ers' starting quarterback in the 2023 season, where he led them to a repeat division title and led the league in multiple passing categories before an appearance in Super Bowl LVIII. Purdy also set the franchise's single season passing yards record and earned his first Pro Bowl selection.

Purdy was born on December 27, 1999, in Queen Creek, Arizona. He played high school football for Perry High School in Gilbert, Arizona. Purdy is the middle child of Shawn and Carrie Purdy. Shawn was a Minor League Baseball player for eight seasons. His older sister Whittney played softball at Southeastern University. His younger brother Chubba later became the starting quarterback at Perry before being recruited to Florida State as a dual-threat quarterback. As a youth, Purdy played quarterback in a flag football league. His father attributed Purdy's later success in part to the faster processing speed required to play flag football; quarterbacks were given seven seconds to dispose of the football before plays were blown dead.

Purdy started his varsity football career during the 2015 season as a sophomore for the newly opened Perry High School. In 2016, the Arizona Interscholastic Association (AIA) adjusted the athletic regions, placing Perry in the 6A Division Premier Region, ranked as the sixth toughest region in the nation. Purdy's performance elevated Perry into the 6A Division AIA State Championship game in 2016 and 2017, losing 65–28 and 48–42, respectively, both to Chandler High School.

Purdy established himself as a football power in Arizona, competing against Chandler Unified School District's more established powerhouse programs such as Chandler High (0–5), Hamilton (4–2) and Basha (2–1). Purdy achieved a 27–13 record at Perry. He was named Gatorade's Football Player of the Year and was The Arizona Republic's high-school player of the year.

Purdy was considered a three-star prospect by 247Sports. He signed his letter of intent to commit to Iowa State University on February 7, 2018, enrolling in June of that year.

Purdy entered his freshman year for the Cyclones in 2018 as the third string to Kyle Kempt and Zeb Noland. He became the starter after Kempt was injured and Noland was ineffective. Overall, Purdy started eight games, completing 146-of-220 passes for 2,250 yards, 16 touchdowns, and seven interceptions for what would prove to be a career-best 169.9 passer rating (sixth best in all NCAA football), and compiling a 7–2 record for the Cyclones. In addition, he rushed for 308 yards and five touchdowns.

During Purdy's sophomore season in 2019, he started all 13 games, compiling a 7–6 record. The year was highlighted by 435 yards and a school-record 510 total yards, along with three passing and three rushing touchdowns against Louisiana-Monroe, five passing touchdowns and one rushing touchdown in a narrow 42–41 loss to the then number 9 Oklahoma Sooners, and 372 yards with three passing touchdowns and one rushing touchdown in a win over Kansas. He passed for a touchdown in 12 consecutive games and completed 39 passes against a single team, Oklahoma State—both school records. Purdy also led the Big 12 Conference in passing yards with 3,982 and was third in total touchdowns, 27 of them passing, which broke George Amundson's 41-year-old school record of 24 total touchdowns.