Galatasaray Ozan trained with the
Galatasaray youth academy, joining in 2011. He signed his first professional contract with Galatasaray on 1 July 2017. Ozan made his professional debut for Galatasaray in a 2–0
Süper Lig win over
Yeni Malatyaspor on 12 May 2018. This made him the first footballer born in the 2000s to play in the Süper Lig. On 24 October 2018, he played his first
Champions League match in a 0–0 home draw against
Schalke 04 in the
2018–19 season.
VfB Stuttgart On 17 January 2019, Kabak moved to
Bundesliga side
VfB Stuttgart where he signed a contract until June 2024. On 3 March, he scored twice in a 5–1 win over
Hannover 96, registering his first senior career goals. In doing so, at the age of 18 years, 11 months and 7 days, he became the youngest Turkish center-back, and third-youngest Stuttgart player to ever score twice in a single Bundesliga match.
Schalke 04 On 30 June 2019, Kabak joined
Schalke 04 on a five-year contract for a fee of €15 million, after Schalke activated a
release clause in his contract. He was a regular performer in his first season with the club, appearing in 28 matches and scoring three goals. In September 2020, he was banned for five games and hit with a €15,000 fine after being caught spitting at
Werder Bremen's
Ludwig Augustinsson. Kabak apologised to Augustinsson via Twitter afterwards, insisting the incident, for which he was shown a red card, was an accident.
Liverpool (loan) On 1 February 2021, Kabak signed for
Liverpool on loan for the remainder of the
2020–21 season. The deal was reportedly worth £1 million, plus potentially £500,000 in add-ons depending on appearances and Liverpool's performance in the Champions League. It also included an option to buy, which was set at approximately £18 million and could rise to £26.5m with add-ons. On 13 February 2021, he made his Liverpool debut in a
Premier League game against
Leicester City, ending in a 1–3 away defeat. On 16 February, he played in a 2–0 away win over
RB Leipzig in the
2020–21 UEFA Champions League, becoming the first Turkish player to appear for an English club in the competition. At the end of the season, Liverpool declined to sign Kabak on a permanent basis.
Norwich City (loan) On 30 August 2021, Kabak returned to England to join newly promoted
Norwich City on a season-long loan deal with the club having an option to make the deal permanent at the end of the season.
TSG Hoffenheim On 23 July 2022, Kabak moved to
TSG Hoffenheim and signed a contract until 30 June 2026. He also has a clause where it shows he could earn up to 8 million in add ons. ==International career==