Rovanperä was born in Jyväskylä, Central Finland. He grew up immersed in rally culture through his father, and garnered international attention at age eight when footage of him driving a rally car circulated online. He participated in his first rally at ten years old. He was coached by several Finnish compatriots, including Esapekka Lappi. Because Finnish law required a driver's license for national competition, Rovanperä initially developed his skills in Latvia, where no such license is required for rally participation.
In 2015, aged 14, Rovanperä competed in Latvia and won the national rally championship in the R2 class. He repeated the feat in 2016 in a Škoda Fabia R5, becoming the youngest driver ever to win a national open-class rally championship at age 16. He also entered the Italian and Finnish Rally Championships, and made his European Rally Championship debut in 2017 at the Rally Liepāja, finishing second overall.
Rovanperä made his WRC debut at the 2017 Wales Rally GB in a Ford Fiesta R5 run by M-Sport, and also won the WRC-2 category at the 2017 Rally Australia. He joined Škoda Motorsport for 2018, recording victories at the Wales Rally GB and the Rally Catalunya, finishing third in the WRC-2 standings. In 2019, driving for Škoda, he won five rounds of the WRC-2 Pro category and sealed the WRC-2 Pro championship title at the Wales Rally GB — his first top-level series title.
Toyota signed Rovanperä for 2020 alongside world champion Sébastien Ogier and Elfyn Evans. He chose car number 69 and scored his first top-class WRC podium at the 2020 Rally Sweden, finishing third. At 19 years, 4 months and 16 days, he became the youngest WRC podium finisher.
In 2021 he won for the first time at the Rally Estonia, becoming the youngest ever WRC event winner at 21 years and 289 days, breaking the record previously held by his team boss Jari-Matti Latvala. He added a second victory at the 2021 Acropolis Rally and finished fourth in the championship.
The 2022 season proved decisive. Rovanperä won six rallies and sealed the world title at the 2022 Rally New Zealand — one day after his 22nd birthday — becoming the youngest World Rally Champion in history. The record he broke had stood since 1995, when Colin McRae won his title at age 27. Rovanperä also became the first Finnish WRC champion since Marcus Grönholm in 2002.
In 2023 he successfully defended his title. He did not win until the fifth round, the Rally de Portugal, but accumulated two further victories and clinched the back-to-back championship at the Central European Rally when title rival Elfyn Evans fell out of contention.
Rovanperä contested only a partial WRC season in 2024 before announcing his retirement from the championship in October 2025. He competed in the Porsche Carrera Cup Benelux in 2024, taking three wins, and pursued single-seater opportunities thereafter. He was set to join the Super Formula Championship in 2026 with KCMG and Toyota Gazoo Racing support, but withdrew after being diagnosed with benign paroxysmal positional vertigo. He subsequently entered the 2026 Formula Regional Oceania Trophy with Hitech.
Rovanperä's ascent reshaped what was considered possible in rally timelines. His back-to-back WRC titles before his 23rd birthday, achieved with a driving style praised for its smoothness and stage-reading intelligence, placed him among the sport's all-time record holders. He was named Autosport International Rally Driver of the Year in both 2022 and 2023.