He voices two of the main characters, Grunkle Stan and Soos. He also voices supporting and recurring characters such as: Old Man McGucket, Bill Cipher, the gnomes, and many others. He has four siblings: his twin sister, Ariel Hirsch, and his half-sisters, Lauren Hirsch., Katrina Hirsch, and Jessica Hirsch.
He places many of his real-life experiences in the show, such as living in Piedmont, California and trick-or-treating with his sister (Ariel) as cats. He also based the series off the summers he spent camping with his great aunt. Both he and his sister wished they would go on the adventures that Mabel and Dipper go on in the show. He based Mabel on his twin sister, Ariel Hirsch, Grunkle Stan off of his Grandpa Stan, and based the entire series loosely on his childhood summers. He gave Mabel a pet pig named Waddles because his sister had always wanted one when she was a child.
Unnamed episode (pilot)
- 101. "Tourist Trapped"
- 102. "The Legend of the Gobblewonker"
- 103. "Headhunters"
- 104. "The Hand That Rocks the Mabel"
- 105. "The Inconveniencing"
- 107. "Double Dipper"
- 108. "Irrational Treasure"
- 109. "The Time Traveler's Pig"
- 110. "Fight Fighters"
- 111. "Little Dipper"
- 112. "Summerween"
- 113. "Boss Mabel"
- 114. "Bottomless Pit!"
- 116. "Carpet Diem"
- 117. "Boyz Crazy"
- 118. "Land Before Swine"
- 119. "Dreamscaperers"
- 120. "Gideon Rises"
- 201. "Scary-oke"
- 202. "Into the Bunker"
- 203. "The Golf War"
- 204. "Sock Opera"
- 205. "Soos and the Real Girl"
- 206. "Little Gift Shop of Horrors"
- 207. "Society of the Blind Eye"
- 208. "Blendin's Game"
- 209. "The Love God"
- 210. "Northwest Mansion Mystery"
- 211. "Not What He Seems"
- 212. "A Tale of Two Stans"
- 213. "Dungeons, Dungeons, and More Dungeons"
- 214. "The Stanchurian Candidate"
- 215. "The Last Mabelcorn"
- 216. "Roadside Attraction"
- 217. "Dipper and Mabel vs. the Future"
- 218. "Weirdmageddon Part 1"
- 219. "Weirdmageddon 2: Escape From Reality"
Roles in Gravity Falls
- Stan Pines
- Old Man McGucket
- Saunterblugget Hampterfuppinshire
- Paper Jam Dipper
- Quentin Trembley
- Cackling skulls
- Sev'ral Timez members
- Bill Cipher
- Yumberjacks drive thru cashier
- Backupsmore University Speaker
- Various others
Alex Hirsch was the creative consultant for Fish Hooks, which he developed for television alongside Maxwell Atoms, where he portrayed Clamantha, her father, Fumble, one of the fish police and a Ferret. He was also a writer and a storyboard artist for The Marvelous Misadventures of Flapjack. He also provided the voice of Officer Concord the Juice Time Juice Box Flavor Cop in the "Terrifying Tri-State Trilogy of Terror" episode of Phineas and Ferb, which is also on Disney Channel. He also provided additional voices to the video game Disney Infinity: Marvel Super Heroes in late 2014. He also voiced Toby Mathews in the Rick and Morty episode, "Big Trouble In Little Sanchez." On January 6, 2015, Hirsch announced that he was developing a new animated series with FOX. 
Alex Hirsch was born and raised in Piedmont, California, and he graduated from the California Institute of the Arts (CalArts) in Los Angeles County, California, in 2007. He also enjoyed going to Oregon, and went there often. He was very fond of The Simpsons as a child, and cited this as one of his main influences. After watching the episode Bart's Comet he attended child therapy. Shortly after graduating, he worked at the digital entertainment studio JibJab and was a writer/storyboard artist on The Marvelous Misadventures of Flapjack. He also served as a creative consultant and helped develop the hit Disney Channel animated series, Fish Hooks, and voices the character Clamantha in the series. Hirsch chose Oregon as the setting for Gravity Falls after spending a summer there during college working for the animation studio Laika.
- In Spring 2007, he created a short film called Off the Wall, which was one of his student films at CalArts. Mike Moon, an animation executive at Disney eventually saw it. Impressed, he asked Alex to pitch the network a television series, which eventually lead to Gravity Falls.
- He based Dipper off of himself.
- Mabel is based off of his twin sister Ariel Hirsch.
- Hirsch has appeared a few times in the show as himself.
- The bottom half of his face is visible among the photos in the opening theme song.
- A caricature of Hirsch is seen in "Bottomless Pit!" riding a unicycle, juggling some balls, at the circus, surrounded by crocodiles.
- A photo of him is posted among "Suspicious Townsfolk" on Dipper's Author board in "Society of the Blind Eye" with the word: Who?
- On the cover of a magazine on Stan and Ford's bunk-bed in "A Tale of Two Stans".
- Inside one of the sky trams in "Roadside Attraction"
- As one of the bodies in Bill's "throne of frozen agony", near the middle in Weirdmageddon 2: Escape From Reality.
- Alex's college roommate was the show's art director, Ian Worrel.
- Alex guest voiced Officer Concord for a special Phineas and Ferb Halloween episode.
- Alex has joked about the rumors that he is hiding occult symbols in the show on multiple occasions, because they are hidden in plain sight.
- Alex has a habit of tweeting misleading "Facts" to trick some fans for fun
- Alex prefers Nintendo over Sega, and his favorite Nintendo game is Kirby's Pinball Land.
- Alex named one of the Manotaurs after his full size adult taxidermy buffalo "Beardy" which he keeps in his office at Disney and insists people sit on when they take tours.
- The number 618 that appears throughout Gravity Falls is a reference to his birthday, June 18th (otherwise 6/18).
- He created the "McGucket Hoax" by leaking a fake photo of Old Man McGucket writing the Journals, which fooled a lot of people into thinking that Old Man McGucket was the Author of the Journals.
- Hirsch is skilled at bird calling and even went on the Late Show with David Letterman at the age of fifteen to share his talent.
- Hirsch has a set of rules regarding Dipper and Mabel's relationship which were created at the start of the series due to the writers frequently and incorrectly assuming that the two didn't get along. So far only two rules were revealed which were,
- The first rule is that "the kids like each other. no matter how much they get on each others nerves, this never changes"
- His Grandfather's ashes were illegally spread in a Vegas casino women's room so he could "see the ladies undress forever"
Articles and interviews
- alexhirsch on Blogger
- Alex Hirsch at deviantART
- Alex Hirsch on Facebook
- Alex Hirsch at the Internet Movie Database