Youth career A native of
Harmonstown,
Dublin, McCormack started out with top Dublin academy
Belvedere, where he earned the opportunity to play for the DDSL representative side at the prestigious
Kennedy Cup in 2017, in which he played a starring role in the final as his side won the competition. He moved to the academy of
League of Ireland club
St Patrick's Athletic in November 2017. His first season with the club saw him winning the league and cup double with the under 15 side. In October 2019, he was part of the under 17 team that won the 2019 league title, beating
Bohemians 4–0 in the final at
Dalymount Park with McCormack scoring twice at
Dalymount Park. On 22 December 2020, he played in the
League of Ireland U19 Division Final, in a 2–1 win over
Bohemians after extra time at the
UCD Bowl to secure a
UEFA Youth League spot for the club. McCormack made his
UEFA Youth League debut on 29 September 2021, scoring his side's goal in a 2–1 loss to
Serbian side
Crvena Zvezda. He was part of the side that won the
League of Ireland U19 Division in 2022.
St Patrick's Athletic 2019 season He made his senior debut for
St Patrick's Athletic on 1 November 2019 in a
Leinster Senior Cup Semi-Final tie away to
Sheriff YC, with McCormack in the starting 11 of a game in which a Pats team made up of academy players won 3–1 after extra time. On 21 December 2019, McCormack signed his first professional contract with the club, signing a 2-year contract until the end of 2021.
2020 season On 26 September 2020, McCormack made his
League of Ireland Premier Division debut when he replaced
Darragh Markey from the bench in the 75th minute of a 2–0 win over
Shelbourne. With the season shortened due to
COVID-19, his only other appearance of the season came on 28 October 2020, coming off the bench for a late cameo in a 3–2 loss away to
Finn Harps.
2021 season The
2021 season proved to be his breakthrough season in senior football, starting his first senior game for the club on 20 April 2021 in a 1–0 win over
Waterford at
Richmond Park. On 6 July 2021, McCormack signed a long-term contract extension with the club, alongside teammate
Darragh Burns. His first goal in senior football came on 22 July 2021, when he headed home an
Ian Bermingham cross to put his side 3 goals up in an eventual 6–0 win over
Bray Wanderers in the first round of the
FAI Cup. With McCormack proving to be a key player off the bench for his club, making 26 appearances in all competitions over the season, he damaged his ankle ligaments playing for the
Republic of Ireland U19's in October 2021, which ultimately resulted in him missing the
2021 FAI Cup Final which his side won on penalties against
Bohemians at the
Aviva Stadium on 28 November 2021.
2022 season McCormack's progress stalled at the beginning of the
2022 season under new manager
Tim Clancy, having to wait until 1 April 2022 for his first appearance for the first team, while returning to play games with the club's under 19 side. On 18 April 2022, McCormack replaced
Jason McClelland from the bench in the 72nd minute away to
UCD with his side trailing by a goal, he scored the equaliser 3 minutes later before assisting the winning goal with a cross from a corner in the 89th minute of a 2–1 victory. On 6 November 2022, he scored the final goal in a 4–0 win over
Shelbourne in the last game of the season.
2023 season Having made just 4 appearances in the club's first 11 games of the season under
Tim Clancy, McCormack regained his place in the team under newly appointed manager
Jon Daly and on 15 May 2023, he scored his first goal of the season, scoring an 84th-minute equaliser 11 minutes after entering the pitch in a 3–2 loss to
Shamrock Rovers at
Tallaght Stadium. On 2 June 2023, he picked up 3 assists in the same game, all coming from corner kick deliveries, in a 3–1 win away to
UCD at the
UCD Bowl. His form under
Daly saw him among the nominees for the
League of Ireland Player of the Month award for June 2023, although he eventually lost out to
Patrick Hoban. On 12 July 2023, McCormack made his first appearance in European competition in a 2–1 loss against
F91 Dudelange in the
first qualifying round of the
UEFA Europa Conference League at the
Stade Jos Nosbaum. On 12 November 2023, McCormack was part of the squad for the
2023 FAI Cup Final, as his side produced a 3–1 win over
Bohemians in front of a record breaking
FAI Cup Final crowd of 43,881 at the
Aviva Stadium. He struggled for consistent game time, featuring in 22 of the club's 36 league games, with just 8 of those coming in the starting team and only 1 start in the second half of the season. This lack of minutes saw him linked with a move to
Dundalk.
Waterford On 29 December 2023, it was announced that McCormack had signed for newly promoted
Waterford for an undisclosed fee. He scored 4 goals in 33 appearances in all competitions in his first season with the club, before signing a new 1 year contract with the club on 13 November 2024.
Wexford loan Having fallen out of favour at Waterford, on 17 July 2025 McCormack was loaned out to
League of Ireland First Division club
Wexford until the end of the season, in search of regular first team football.
Bray Wanderers On 13 February 2026, McCormack joined
League of Ireland First Division side
Bray Wanderers. He scored his first goal for the club on 13 March 2026, in a 2–1 victory at a home to
UCD at the
Carlisle Grounds. After an impressive start to his career with Bray, McCormack was named
League of Ireland First Division player of the month for March. On 8 May, McCormack scored his first career
hat-trick scoring three times to give Bray a 3–0 half time lead in a 5–1 win at home to
Cobh Ramblers. ==International career==