Carpenter was born on May 11, 1999, in Lehigh Valley, Pennsylvania.

Carpenter booked her first acting role in 2011, a guest role on the NBC drama series Law & Order: Special Victims Unit. She played a young rape victim interviewed by Detective Elliot Stabler (Christopher Meloni). Around the same time, she performed live on the Chinese television station Hunan Broadcasting System, for the Gold Mango Audience festival. She performed Etta James' "Something's Got a Hold on Me", in the style of Christina Aguilera from the movie Burlesque. Less than two years later, Carpenter booked a series recurring role on Fox's The Goodwin Games as Young Chloe, a series regular role on Disney Channel pilot Gulliver Quinn and the ABC pilot The Unprofessional.

She portrayed young Merrin in the 2013 film Horns. Carpenter performed "Smile" for the album Disney Fairies: Faith, Trust And Pixie Dust"; the song charted on Radio Disney. Her song "All You Need" is featured on the Sofia the First Soundtrack.

In January 2013, Carpenter was cast as Maya Hart in the Disney Channel series Girl Meets World, opposite Rowan Blanchard. The series is a sequel to the 1993–2000 ABC series Boy Meets World. On March 14, 2014, Carpenter's debut single, "Can't Blame a Girl for Trying", premiered on Radio Disney, and was released on iTunes later in the day. The song is the title track on her debut EP which was released on April 8 and was generally well received. Carpenter is featured on the Girl Meets World theme song, "Take On The World", which also features her co-star Blanchard. Carpenter performed the song "Stand Out" in the Disney Channel Original Movie How to Build a Better Boy, which premiered August 15, 2014, on Disney Channel. On July 20, 2014, Carpenter contributed lead vocals to Disney Channel Circle of Stars' cover version of "Do You Want to Build a Snowman?" In January 2015, it was announced that Carpenter, along with Sofia Carson, would star in a Disney Channel Original Movie, then titled Further Adventures in Babysitting, based on the 1987 movie Adventures in Babysitting.

In August 2015, it was reported that Carpenter had begun work on her second album. On November 5, 2015, she unveiled the artwork for her new single, "Christmas the Whole Year Round", which was released a week later. On February 2, 2016, Carpenter announced via social media that a new single, "Smoke and Fire", would be released on February 19, 2016. Speaking of the single, Carpenter said: "Smoke and Fire was the first story that I was waiting to tell out of the many stories from the second album... I kind of write wherever I go. I'm always writing down things in my phone and in my notes on stuff that inspired me and stuff that I see in everyday life, or even just fun words." While this song was expected to be on her second album, it does not appear on the tracklist due to Carpenter feeling her "evolution" came after the song. On July 29, 2016, Carpenter released "On Purpose", the first single from her second album. On September 3, 2016, Carpenter announced the name of the album as Evolution and announced her first tour, the Evolution Tour, the next day. On October 11, 2016, she announced that the tour had sold out, and on October 14, the album was released. In November 2016, she was picked as Elvis Duran's Artist of the Month appearing on NBC's Today show with Hoda Kotb and Kathie Lee Gifford performing her song "Thumbs".

In 2017, Carpenter recorded the theme song for the series Andi Mack, titled "Tomorrow Starts Today". On April 17, 2017, she performed her single "Thumbs" on The Late Late Show with James Corden. She collaborated with The Vamps and Mike Perry for the single "Hands", which was released on May 19, 2017. In 2017, she toured Europe with The Vamps, and she will be doing a summer tour with New Hope Club. On October 13, 2017, Lost Kings released a single called "First Love" featuring Sabrina Carpenter. Her single "Why" was released on July 7, 2017. It was produced by Jonas Jeberg. In 2017, Carpenter sang "You're a Mean One, Mr. Grinch" on Lindsey Stirling's holiday album Warmer in the Winter. In December 2017, Carpenter released a cover of "Have Yourself a Merry Little Christmas".