Early career Harder played for Team Viborg and
IK Skovbakken in her native Denmark's
Elitedivisionen. Skovbakken had made Harder and her contemporary
Sofie Junge Pedersen contracted players in April 2010, in recognition of their exceptional potential.
Linköpings FC Harder chose Swedish club
Linköpings FC for her next destination because she wanted a new challenge, but also because she wanted to remain in
Scandinavia. In September 2013 she scored all four goals in Linköping's 4–1 win at
relegation-bound
Sunnanå SK. In the
2015 Damallsvenskan season, Harder scored 17 goals in 22 appearances for Linköping, winning a series of national awards including Årets Anfallare () and Årets Allsvenska Spelare (). At the annual awards gala, she shared the stage with male winner
Zlatan Ibrahimović and was described as "hyper-talented" and "world-class" by Swedish national coach
Pia Sundhage. Harder was also voted
Danish Football Player of the Year in 2015. In June 2016, Harder was among 30 local worthies to be named in a Wall of Fame by
Linköping Municipality. Harder enjoyed further success in the
2016 Damallsvenskan season, retaining the League Player of the Year award. Her 23 league goals secured the Top Goalscorer award and helped Linköping win the Damallsvenskan title. By now a transfer target for the biggest clubs in
women's football, Harder's agent announced in November 2016 that she would be leaving Linköping for a new challenge.
VfL Wolfsburg In December 2016, it was announced that Harder had signed a two-and-a-half-year contract with
VfL Wolfsburg running from January 2017. In all four seasons with the team, Harder won the
Bundesliga and
German Cup double. She was top scorer in the league twice: in the
2017–18 season with 17 goals scored, and in the
2019–20 season with 27 goals. Thanks to these performances, she won the
UEFA Women's Player of the Year Award twice for the 2017-18 and 2019-20 seasons. She also played in two
Champions League finals (
2018 and
2020), losing both to
Lyon. In 2020, she was elected best forward of the Champions League and best player of the German Championship.
Chelsea On 1 September 2020, Harder signed for
Chelsea on a three-year contract for a world-record fee for a female footballer, reportedly in excess of £250,000. In the
2020–21 Champions League quarter-finals, she scored in both legs against her former club VfL Wolfsburg. In the group stage of the
2022–23 Champions League she scored a hattrick against
KF Vllaznia Shkodër. On 18 November 2022 she suffered a serious thigh injury on national team duty against
Austria that required surgery and sidelining her for five months. She made her comeback against
Barcelona in the Champions League semi-final on 22 April 2023. In the FA Cup final against
Manchester United she gave the assist for the victory goal for Sam Kerr in front of a record crowd of 77,390 people.
Bayern Munich On 1 June 2023, it was announced that Harder, along with partner and former Chelsea teammate
Magdalena Eriksson, had signed for
Bayern Munich on a three-year deal. She made her debut for Bayern against
SC Freiburg and scored her first goal against
1. FC Köln. In the next game against
SGS Essen, she scored her second goal, but collided with the goalkeeper and was subbed out with a knee injury after 17 minutes. With a
medial collateral ligament injury she was out for over two month and made her comeback in December 2023 against
1. FC Nürnberg. After the winter break, she quickly returned to her old form. She provided assists against Freiburg and Frankfurt, and scored twice against Leipzig. In the top match against her former club, she scored to make it 1–0 and set up Lea Schüller for the 3–0 goal with a through ball. Harder scored a
hat trick against Nuremberg, and on the final matchday, away against TSG Hoffenheim, she scored again. Bayern thus won its sixth German championship. She finished the season as the club's second-best goalscorer alongside
Jovana Damnjanović, with nine league goals and 13 goals in total. Harder's
2024–25 season with Bayern was very successful: the team won the double for the first time with the German championship and the DFB Pokal. With this title win, Harder made football history, as she is the first female footballer to have won the championship ten years in a row in different leagues. She was the club's top scorer with 23 goals in all competitions including 14 league goals and was named player of the season. In May 2025, she also won the newly created
World Sevens Football tournament on a small field with Bayern. On 19 December 2025, Harder and Eriksson extended their contracts until 30 June 2028. ==International career==