In 2007, Stoessel had a role in the first season of the popular Argentine children’s telenovela, Patito Feo, as “Martina”, one of Fito Bernardi’s assistants. She also played the role of “Anna” in a flashback episode in the same series.

In 2011, Stoessel recorded the Spanish version of the Shannon Saunders’ song, “The Glow”, called “Tu Resplandor”; the song was included on the album, Disney Princess: Fairy Tale Songs. She performed the song at an event for Disney Channel Latin America called Celebratón on 31 December 2011. The song was later released on an album for the series in March 2012.

Stoessel’s father presented an unrelated project to Disney Channel producers, who later informed him about auditions for the lead role for the network’s upcoming television series, Violetta. In late 2011, after an intense casting process, Stoessel obtained the principal role in the series, a tween-oriented musical series launched as a co-production between Disney Channel Latin America, Europe, Middle East and Africa. The show’s first season began production in Buenos Aires in 2012. Stoessel played the titular character, Violetta Castillo, during all three seasons of the show. She sang the series’ theme song, “En Mi Mundo”, which was later released as a single on 5 April 2012 to promote the show. Subsequently, she recorded the Italian version, “Nel Mio Mondo” and the English version, “In My Own World”. Both songs were used as the theme songs for the series in its international broadcasts in Italy, the United Kingdom and the United States via Netflix. For this role Stoessel won an award for “Female Newcomer” in the 2012 edition of the Kids’ Choice Awards Argentina and was also nominated for the U.S. version, the Nickelodeon Kids’ Choice Awards, in the “Favorite Latin Artist” category.

From 2012 to 2014, Stoessel participated in the recording of albums featuring music from all three seasons of Violetta. Stoessel also participated in the television programs The U-Mix Show and Disney Planet for Disney Channel Latin America. In 2014, Stoessel voiced a small role for the Italian dubbed version of the Disney animated film Monsters University. In May 2014, Stoessel released her first book, a co-authored biography called “Simplemente Tini”, about on her upbringing and eventual rise to international popularity. The same month, Stoessel held a free musical concert near the Monument to the Carta Magna and Four Regions of Argentina, organized by the city government of Buenos Aires, under the slogan “Cuidemos el planeta”. In September 2014, Stoessel performed at a charity soccer match Partido Interreligioso por la Paz, convened by Pope Francis at the Stadio Olimpico in Rome where she sang “Nel Mio Mondo” and the cover version of John Lennon’s song “Imagine”.

On 10 August 2013, Stoessel performed, along with the cast of Violetta, at the UNICEF television charity event Un sol para los chicos, where she sang the songs, “Ser Mejor” and “En Mi Mundo”. In 2013, Stoessel recorded “Libre Soy” and “All’Alba Sorgerò”, the Spanish and Italian versions of the pop version of “Let It Go”, the closing credits song from the Disney animated film Frozen.

Stoessel and some of the cast members of Violetta filmed the movie, Tini: The Movie. The movie was filmed in between concert stops for the television series’ final international tour. Production began on 7 October 2015 and ended in mid-December 2015, where the movie filmed in various international locations, including Sicily, Cádiz, Spain, Madrid, and Buenos Aires. A teaser trailer featuring scenes from the movie was released in late December 2015. The film was released in various Latin American and European countries. It was to be released in Argentina on 14 July 2016, but was released earlier on 2 June 2016.

On 21 August 2015, it was announced that Stoessel had signed a recording deal with Hollywood Records to release her own solo material under the name “Tini”. From January 2016 to early March 2016 she recorded her debut album in Los Angeles, California. Her debut album, TINI (Martina Stoessel), was released worldwide on digital and physical formats on 29 April 2016. The album contains two discs: one which serves as the soundtrack from Tini: The Movie and Stoessel’s solo album of Spanish and English language songs. Stoessel announced that “Siempre Brillarás” would be the lead single used to promote the release of Tini: The Movie. The song was available to fans on 25 March 2016 with the pre-order purchase of her debut album. The song was also recorded in English and was released under the title, “Born to Shine”. The music video for “Siempre Brillarás”, featuring scenes from Tini: The Movie, was released on 25 March 2016. The music video for the soundtrack’s second promotional single, “Losing the Love”, was released on 6 May 2016, and its music video included clips from the film. Stoessel performed songs from her debut album at her first showcase as a solo artist at La Usina del Arte in Buenos Aires on 12 June 2016. The showcase was filmed and broadcast on her official YouTube channel from 22 to 28 August 2016. On 24 June 2016, Stoessel released her first solo single, “Great Escape”, along with the Spanish-language version of the song, “Yo Me Escaparé”. The music video for “Great Escape” was filmed in Buenos Aires and later released on 8 July 2016. On 14 October 2016, Stoessel released the deluxe edition of her debut album, which includes “Yo Me Escaparé” and the Spanish-language version of the song “Got Me Started”, “Ya No Hay Nadie Que Nos Pare”, with vocals from Colombian singer Sebastián Yatra. Stoessel released “Got Me Started”, along with “Ya No Hay Nadie Que Nos Pare”, as her second solo single to coincide with the release of the deluxe edition of her album. The music video for “Got Me Started” was released on 8 December 2016, while the video for “Ya No Hay Nadie Que Nos Pare” was released on 19 January 2017. Stoessel’s third solo single, “Si Tú Te Vas”, was released on 5 May 2017, alongside the music video for the song. On 18 March 2017, Stoessel began her first solo concert tour, Got Me Started Tour, starting from Europe and then heading on to Latin America.

Stoessel resides in San Isidro, Buenos Aires with her parents and her brother. She is fluent in Spanish, Italian, and English. On 17 November 2016, Stoessel was named an honorary ambassador of the world peace by fellow human rights activist Adolfo Pérez Esquivel and Guatemalan political activist Rigoberta Menchú, at the Red voz por la paz ceremony in Buenos Aires.

Stoessel’s second album titled Quiero Volver was released on 12 October 2018. The collaboration between Stoessel and Venezuelan singer Nacho titled “Te Quiero Más” was released on 13 October 2017 as the lead single from the album. In December 2017, Stoessel made a guest appearance as herself in an episode of the telenovela Las Estrellas, and she was featured in a remix of “Lights Down Low” by MAX, titled “Latin Mix”. On 6 April 2018, Stoessel released “Princesa”, a duet with Karol G, as the second single from her second album. The single became Stoessel’s first single to top the national chart in Argentina. On 22 June 2018, Stoessel released “Consejo de Amor”, featuring Colombian folk-rock band Morat, as the third single from her second album. On 26 July 2018, Stoessel was featured alongside Flo Rida on a remix of Álvaro Soler’s hit single “La Cintura”. On 3 August 2018, Stoessel released the title track “Quiero Volver”, a duet with Sebastián Yatra, as the fourth single from her second album. On 24 August 2018, Stoessel was featured alongside Colombian singer Greeicy in a remix of the song “Lo malo” by Spanish singers Aitana and Ana Guerra. In September 2018, Stoessel announced her second concert tour, Quiero Volver Tour, that began on 13 December 2018 at Estadio Luna Park in Buenos Aires. On 2 November 2018, Stoessel released “Por Que Te Vas”, a collaboration with Cali y El Dandee, as the fifth single from her second album. In the same month, she was featured alongside Chelcee Grimes and Jhay Cortez on “Wild”, the song from Jonas Blue’s debut album Blue, released as a single in February 2019.

In August 2018, it was announced that Stoessel had joined La Voz… Argentina as a coach for the reality competition show’s second season; Stoessel is the youngest judge on any incarnation of The Voice franchise. Stoessel voiced Moxy in the Spanish dubbed version of the animated musical comedy film UglyDolls, released in May 2019.

The collaboration between Stoessel and Greeicy titled “22” was released on 3 May 2019 as the first single from Stoessel’s third album. The song peaked at number eight on Argentina Hot 100 and became Stoessel’s first top-ten single on the chart. On 14 June 2019, Stoessel was featured on “Sad Song”, a collaboration with Swedish DJ Alesso. On 26 July 2019, Stoessel released “Suéltate El Pelo” as the second single from her third album. On 6 September 2019, Stoessel released “Fresa”, a collaboration with Colombian singer Lalo Ebratt, as the third single from her third album. The song peaked at number three on Argentina Hot 100, becoming Stoessel’s first top-five single on the chart. On 11 October 2019, Stoessel released “Oye”, a duet with Sebastián Yatra, as the fourth single from her third album. The song debuted at number three on Argentina Hot 100, becoming Stoessel’s second top-five single on the chart in a row. On 10 January 2020, Stoessel released “Recuerdo”, a collaboration with Venezuelan duo Mau y Ricky, as the fifth single from her third album. The collaboration between Stoessel and Colombian producer Ovy on the Drums titled “Ya no me llames” was released on 25 March 2020. Stoessel appeared alongside Dutch DJ and producer R3hab and Mexican pop rock band Reik in a song titled “Bésame (I Need You)”, released on 5 June 2020. On 15 July 2020, Stoessel appeared alongside fellow trap artist Khea on “Ella Dice”, the sixth single from her third album. The song peaked at number four on Argentina Hot 100, becoming Stoessel’s third top-five single on the chart. On 3 September 2020, Stoessel appeared alongside Lola Índigo on the remix of María Becerra’s song titled “High”. The remix peaked at number two on Argentina Hot 100, becoming Stoessel’s fourth top-five single on the chart. On 24 September 2020, Stoessel released “Duele”, featuring trap artist John C, as the seventh single from her third album. The song peaked at number ten on Argentina Hot 100, becoming Stoessel’s sixth top-ten single on the chart. On 29 October 2020, Stoessel appeared alongside Alejandro Sanz on “Un Beso en Madrid”, the eighth single from her third album.

In May 2019, it was announced that Stoessel had joined the reality talent show Pequeños Gigantes Argentina as a judge. In May 2020, Stoessel released, in collaboration with YouTube, a docuseries titled Tini Quiero Volver Tour. It shows behind the scenes and concert footage from Stoessel’s Quiero Volver Tour, and follows her professional life during the tour. The series debuted on 22 May 2020. In October 2020, Stoessel served as a key advisor on the Spanish version of The Voice for its seventh season. Stoessel is also set to star in a Chinese period drama film titled The Diary, directed by Jackie Chan, with the release date yet to be announced.