Parents are David Efron and Starla Baskett.
On the Billboard Hot 100 chart of 2006-2002-2011, Zac had five simultaneous song credits. The songs were "Get'cha Head in the Game" (solo), three duets with Vanessa Hudgens ("Breaking Free", "Start of Something New" and "What I've Been Looking For") and "We're All in This Together" credited to the High School Musical (2006) cast. All tracks were from the soundtrack of "High School Musical".
The Zac Efron-Vanessa Hudgens duet "Breaking Free" (from High School Musical (2006)) made the fastest climb in the history of the Billboard Hot 100, leaping from 86 to 4 in one week (2006-2002-2011).
With the popularity of High School Musical (2006), he had to change his phone number after getting numerous calls from fans.
Zac's most prized possession is his autographed baseball collection.
He donated many items to Rocky Stone to be given to less fortunate kids as part of the Toy Mountain Campaign.
Attended the World Cup in Germany with Corbin Bleu.
The first concert he ever went to was a concert of The Wallflowers.
Has one sibling, younger brother Dylan Efron.
Simon Cowell offered him a record deal but he turned it down saying, "...acting is my main priority".
Named #93 on Empire Magazine's 100 Sexiest Movie Stars. 
(January 15, 2008) Had his appendix removed and is recuperating.
His favorite movie is The Goonies (1985).
Ranked #24 on interview magazines Hollywood faces to watch "Future Stars of Tomorrow".
Was ranked #26 on Entertainment Weekly's '30 Under 30' the actors list. 
Was ranked #2 on TV Guide Top 10 Teen Star Countdown. 
Was ranked #15 on Moviefone's 'The 25 Hottest Actors Under 25'. 
His acting idol is Johnny Depp.
Is a fan of Flight of the Conchords.
Is a fan of comic books and manga, including Death Note, Bleach, Naruto, Dragonball Z and Shonen Jump.
Recognized by Time Magazine in the 2009 Time 100 as one of the world's 100 most influential people.
Originally auditioned for the role of "Peter Pan" in the 2003 live action movie, Peter Pan (2003), but Jeremy Sumpter got it, instead.
His singing voice in the first High School Musical (2006) was actually that of singer/songwriter/actor Drew Seeley.
Has worn a white shirt with red sleeves in all three High School Musical movies.
His favorite movies are Dumb and Dumber (1994), Knocked Up (2007), The 40 Year Old Virgin (2005), Die Hard (1988), and "Bourne" series.
His favorite musicians are The Postal Service, The Shins, The Gorillaz and John Mayer.
Briefly vacationed in Rio de Janeiro, Brazil, with Vanessa Hudgens. [February 2009]
Coached by actor Aaron Michael Metchik and his mother Robyn Metchik.
Graduated Arroyo Grande High School with actors Bryce Blue and JR Garcia.
His favorite actors are Brad Pitt, Christian Bale, Leonardo DiCaprio, and Jack Black.
(2006-2010) Was in a relationship with Vanessa Hudgens.
Friends with actors Ashley Tisdale, Corbin Bleu, Bryce Blue, JR Garcia, and Aaron Michael Metchik.
Learned how to ride a motorcycle after a chance party meeting with bike enthusiast Tom Cruise, who offered to act as Efron's coach.
Zac's last name, "Efron", which is Hebrew, is taken from a biblical place name. Zac's paternal grandfather, Harold Efron, was born in New York, the son of Nasko Efron and Dworja Klein, who were Jewish emigrants from Bocki, Poland, and Zac has described himself as Jewish. Zac's other ancestry includes English, German, Scottish, one sixteenth Irish, and very distant Dutch and Belgian (Flemish).
It is said that he has a physical resemblance with Romeo and Juliet (1968) star Leonard Whiting, and with actors Logan Lerman, Kevin Zegers, Robby Benson, and Tony Curtis.
Has two Australian Shepherds named Dreamer and Puppy, and a Siamese cat named Simon.
Completed filming Charlie St. Cloud (2010). [October 2009]
New Orleans, LA. Wrapped up the shooting on 'Nicholas Sparks'' novel-based movie called The Lucky One (2012). [December 2010]
Los Angeles, CA: Filming the movie "Neighbors". [April 2013]
Filming High School Musical 3: Senior Year (2008) in Salt Lake City, Utah. [May 2008]
Filmed High School Musical 2 (2007). 
Filming Charlie St. Cloud (2010) in Vancouver, B.C. [August 2009]
Austin, Texas - Wrapped "Parkland" [February 2013]
New York City, NY - Wrapped "That Awkward Moment". [January 2013]
Los Angeles, CA: Finished filming the movie "Neighbors". [May 2013]
New Orleans, LA, USA: - Wrapped on The Paperboy (2012). [September 2011]
Currently filming 17 Again (2009). [January 2008]
DeKalb, IL, USA: Wrapped the untitled Ramin Bahrani film. [October 2011]
Broke his jaw when he fell in his LA home after slipping in a puddle of water. [November 2013]
Entered rehab for cocaine abuse. [April 2013]
Has been compared in appearance to Tyrone Power by reviewers in the Chicago Tribune, SF Gate, Casa Magazine, and the New Yorker magazine.
Named as the #5 Sexiest Man in Glamour's list of "50 Sexiest Men" in 2011.
People magazine named him as having one of the "50 Most Amazing Bodies" in 2010 and as one one of the "Most Beautiful" in 2011.
Has a tattoo of two feathers on his right arm.
His maternal great-grandmother, Helene (Durgan) Glidden, wrote the 1951 book The Light on the Island. The book is about Helen's early years growing up on Patos Island, Washington, where her father, Edward Durgan, was the lighthouse keeper from 1905 to 1913.
Gregory Harrison had a crush on his mother, Starla Baskett, when they were in high school.
He is a vegan.