Hirsch was born in the Bronx, New York, the son of Sally (née Kitzis) and Joseph Sidney Hirsch, an electrician. Hirsch was raised Jewish and his father was an immigrant from Russia. Hirsch attended De Witt Clinton High School and later earned a college degree from the City College of New York in physics. He was married to his first wife from 1956 to 1958. He married Bonni Sue Chalkin in 1992 and divorced her in 2003. Hirsch has three children: Alexander, born 1966, Montana Eve born in the 90's and London, his youngest son.

His first major television appearance was in a mini series titled, THE LAW, which springboarded Judd's career in 1974. For his performance in Taxi, in 1981 and again in 1983, Judd Hirsch won the Emmy Award for Lead Actor In a Comedy Series. Hirsch went on to play the title character on the modestly successful sitcom Dear John and in 1989 won a Golden Globe Award for Best Actor in a Television Series in a Comedy or Musical for this role. He later teamed with Bob Newhart in the short-lived comedy George and Leo. He had also previously starred for one season in the series Delvecchio, playing a police detective (1976-1977).

In motion pictures, Hirsch received a nomination for the Academy Award for Best Supporting Actor for his role in 1980s Ordinary People. Other films in the 1980s include the 1983 drama Without a Trace, the 1984 dramedies Teachers and The Goodbye People, and the 1988 drama Running on Empty directed by Sidney Lumet and co-starring River Phoenix. In 1996 Hirsch portrayed the father of Jeff Goldblum's character in Independence Day, and in 2001 he appeared in the acclaimed A Beautiful Mind.

Hirsch co-starred on the CBS Television drama NUMB3RS as Alan Eppes, father of FBI agent Don Eppes (Rob Morrow) and Professor Charlie Eppes (David Krumholtz). Hirsch and Krumholtz also played father and son in Conversations with My Father, a Herb Gardner play for which Hirsch won the Tony Award for Best Performance by a Leading Actor in a Play. Krumholtz credits Hirsch with jump-starting his career after Hirsch chose him during the audition process for Conversations. Other noteworthy stage performances include The Hot l Baltimore, Talley's Folley, and his starring role in I'm Not Rappaport, in which Hirsch also won a Tony Award in 1986.

More recently, Hirsch has guest-starred on episodes of Studio 60 on the Sunset Strip and Law & Order: SVU, among others, and lent his voice to the animated programs Tom Goes to the Mayor and American Dad! In 1999, he reprised his role from Taxi for a brief moment in Man on the Moon, the biopic of his co-star from Taxi, Andy Kaufman (portrayed by Jim Carrey).

Frank Langella (1975) · Judd Hirsch (1976) · Bob Dishy (1977) · Jeffrey DeMunn (1978) · George Rose (1979) · David Rounds (1980) · Brian Backer (1981) · Željko Ivanek / Adolph Caesar (1982) · Alan Feinstein (1983) · John Malkovich (1984) · Barry Miller / Charles S. Dutton (1985) · Joseph Maher (1986) · John Randolph (1987) · B. D. Wong (1988) · Peter Frechette (1989) · Charles Durning (1990) · Kevin Spacey (1991) · Laurence Fishburne (1992) · Joe Mantello / Stephen Spinella (1993) · Jeffrey Wright (1994) · Nathan Lane (1995) · Martin Shaw (1996) · Brian Murray (1997) · Alfred Molina (1998) · Kevin Anderson (1999) · Roy Dotrice (2000)

Complete list · (1975-2000) · (2001-present)

Jack Albertson (1976) · Carroll O'Connor (1977) · Carroll O'Connor (1978) · Carroll O'Connor (1979) · Richard Mulligan (1980) · Judd Hirsch (1981) · Alan Alda (1982) · Judd Hirsch (1983) · John Ritter (1984) · Robert Guillaume (1985) · Michael J. Fox (1986) · Michael J. Fox (1987) · Michael J. Fox (1988) · Richard Mulligan (1989) · Ted Danson (1990) · Burt Reynolds (1991) · Craig T. Nelson (1992) · Ted Danson (1993) · Kelsey Grammer (1994) · Kelsey Grammer (1995) · John Lithgow (1996) · John Lithgow (1997) · Kelsey Grammer (1998) · John Lithgow (1999) · Michael J. Fox (2000)

Complete list: (1950–1975) · (1976–2000) · (2001–present)

Flip Wilson (1970) · Carroll O'Connor (1971) · Redd Foxx (1972) · Jack Klugman (1973) · Alan Alda (1974) · Alan Alda (1975) · Henry Winkler (1976) · Henry Winkler (1977) · Robin Williams (1978) · Alan Alda (1979) · Alan Alda (1980) · Alan Alda (1981) · Alan Alda (1982) · John Ritter (1983) · Bill Cosby (1984) · Bill Cosby (1985) · Bruce Willis (1986) · Dabney Coleman (1987) · Michael J. Fox/Judd Hirsch/Richard Mulligan (1988) · Ted Danson (1989)