JT was born and raised in Miami, growing up in Carol City and Liberty City.^[1] JT is the eldest of her mother’s three children and among the youngest of her father’s 16, the rest of whom were her stepmother’s children. When she was about five years old, JT’s mother was incarcerated, and she went to live with her father and stepmother in Carol City, where she often felt ostracized. “I always felt like I was the black sheep in my family,” JT told Angie Martinez in a 2023 interview. But despite that, she found a way to connect with her siblings.

JT was in a rap group when she was a little girl, called The Protegees, with her sisters and brothers. Throughout her teens, JT alternated between living with her aunt in Liberty City and sleeping on the couches of her friends' homes. One such friend was Caresha Brownlee, also known as Yung Miami, who would eventually make up the other half of the City Girls.^[2] JT was known among her friends for the freestyle raps she would come up with in her car and occasionally post on social media. Knowing she had potential but too shy to record and release a song all by herself, JT recruited Brownlee to rap with her. JT and Yung Miami uploaded their first song, “Fuck Dat Nigga,” to SoundCloud in August of 2017.^[3]The song was a diss track towards their ex-boyfriends for not giving them money when they asked. The song went viral, leading them to sign with Quality Control Music.

In her early 20s, JT studied Fashion Merchandising with dreams of becoming a designer. But she wasn't fan of the broke college student lifestyle, and her dreams weren’t panning out as quickly as she’d hoped. JT worked jobs at the Miami Seaquarium, Burger King and Whole Foods, but the jobs simply weren't paying enough. Her friends would borrow her car for the weekend and mysteriously return with bags full of designer clothes and shoes obtained through credit card scams, one day, JT joined them.

The City Girls released their debut mixtape, Period, in May 2018.^[4] In July 2018, the duo were launched into mainstream recognition after an uncredited feature on Drake's "In My Feelings."^[5]In November 2018, the City Girls released their debut album, which included features from Cardi B, Lil Baby and Jacquees. On June 19, 2020, City Girls' second studio album, City on Lock, leaked in its entirety online.^[6] It was officially released the following day.^[7] The album's first single, "Jobs", was released hours before the album alongside a music video.^[8] The album includes guest appearances from Yo Gotti, Doja Cat, Lil Durk and Lil Baby. Their third studio album, RAW, was released in October 2023.

JT's debut single as a solo artist, "No Bars", was released on July 14, 2023.^[9] It is her second solo song altogether, her first being "JT First Day Out" in 2019.^[9] It placed at #25 on the BillboardBubbling Under Hot 100 chart.^[10] No Bars also served as the fourth single for RAW. In February 2024, JT released her single "Sideways", which debuted at #7 on the Billboard Bubbling Under Hot 100.^[11]

JT also features as a solo artist on records including Summer Walker's "Ex for a Reason" (2021), the "Queen Mix" of Nicki Minaj's "Super Freaky Girl" (2022), and Kali Uchis' "Muñekita" (2023).^[12]

On March 9, 2024, JT announced her 14-show solo tour, starting on March 23 in Houston, Texas, and ending April 27 in Kansas City, Missouri.^[13]

On March 24, 2024, JT announced her debut solo mixtape, City Cinderella.^[14] On March 29, 2024, JT and Doechii released their collaboration single "Alter Ego".^[15] JT teased a snippet of her single "Okay" as a part of her tour, which later went viral on social media.^[16] "Okay" was released on April 26.^[17] On May 7, 2024, "Okay" charted on the Billboard Hot 100 at #74, marking JT's first ever solo charting record.^[18] An extended version with an extra verse was released three days later to celebrate this and further generate anticipation for City Cinderella.^[19] On June 28, 2024, JT released a remix of "Okay" featuring a verse from rapper Jeezy.^[20] City Cinderella was released on July 19, 2024.^[21]

JT has been dating rapper Lil Uzi Vert since 2019.^[22]

In summer 2023, JT launched the merchandising retailer and lifestyle brand, thegirljtworld.^[23]

Shortly after the release of the 2017 debut single, "Fuck Dat Nigga", JT was arrested and convicted of aggravated identity theft on fraudulent credit card charges, and was sentenced to 2 years in federal prison. Following a pushback of her surrender date, JT turned herself in to the authorities on June 29, 2018, and began serving her sentence while being held at FCI Tallahasseein July 2018.^[24] She was slated to be released March 21, 2020.^[24] As she awaited her release, JT was transferred from FCI Tallahassee to a halfway house in Atlanta on October 8, 2019.^[25]During her stay in the halfway house, she was able to leave the house during the day to work and visit family and friends.^[25] To celebrate her release, JT released a track titled "JT First Day Out".^[26] JT was officially released from federal custody on March 7, 2020.^[27]