Hansen moved from Brøndby to Liverpool in 2006, where he made his Liverpool Academy debut against Chelsea's academy, in a 2–0 win on 16 January 2007. Hansen was the member of the Liverpool Under 18s who won the FA Youth Cup in 2007, even though he missed the second leg of the FA Youth Cup Final with a broken finger. Following this, Hansen was promoted to the reserve. Hansen signed his first professional with the club in July 2007, signing a two-year deal. After spending a number of years in Liverpool's reserves, Hansen signed a one-month loan contract with Bradford City on 27 July 2011. He made his senior debut on 6 August 2011. On 21 August, it was announced that Hansen would return to Liverpool at the end of the month-long deal, after the two clubs failed to agree to an extension. During that time he played in all 4 of Bradford City's league games.
Hansen moved back to Denmark on 31 January 2012, signing for Viborg FF. It took until on 5 April 2012 for Hansen to make his Viborg FF debut, in a 2–2 draw against Akademisk BK. Hansen's brilliant display in recent games led Manager Søren Frederiksen commenting on his performance that he's one of the best goalkeeper to play in the Danish 1st Division. Even opposition managers praised Hansen's performance. In the second half of the season, Hansen made eleven appearance for the club. His full second season at Viborg FF saw him made 32 out of 33 appearance and helping the club get promoted to the top division despite suffering a back injury in the winter. It was announced in late-December 2012 that Hansen intended not to renew his contract at Viborg FF. Despite linked with a move to France it was announced in May 2013, it was confirmed that he would join FC Nordsjælland on a three-year contract, keeping him until 2016. After being on the bench in the opening game of the season, Hansen made his Nordsjælland debut on 26 July 2013, in a 1–1 draw against his former club, Viborg FF. Hansen also played in the Champions League qualification against Zenit Saint Petersburg but they proved to be too strong and failed to win either legs losing 1–0 and 5–0 respectively. During the season, Hansen find himself fight over a first choice goalkeeper with Jesper Hansen, Jannich Storch, Thomas Villadsen and David Jensen. Following this, Manager Kasper Hjulmand reassured that Hansen shall be the club's first choice goalkeeper. Hansen continued to be the first choice goalkeeper for the club by the end of the first half of the season, but was dropped in favour of Jensen, who was used for the rest of the season. Hansen went on to make fifteen appearance for the club in his first season. Hansen caused controversy after calling the club's personal trainer Mathias Zangenberg a 'monkey', for which he later apologised. After one season, the club's chairman announced his intention to sell Hansen.
In early June, Hansen was linked with a move abroad, most likely in Netherlands. The club was looking for a new goalkeeper following Gino Coutinho's departure. On 11 July 2014, it was announced that Hansen had signed a two-year deal with Dutch Eredivisie side ADO Den Haag. Hansen made his ADO Den Haag in the opening game of the season, in a 1–0 loss against Feyenoord. Hansen continued to be in the first choice goalkeeper by the first half of the season until he suffered a hand injury that saw him missed one match. After resuming his training, Hansen made his return to the first team on 17 January 2015, but after conceding two goals, which resulted a 2–2 draw, Hansen immediately left the stadium. He later explained his actions on his Twitter account. On 24 April 2015, against Vitesse Arnhem, Hansen provided an assist for Michiel Kramer, which turned out to be a winning goal. However, Hansen was dropped to the bench ahead of the match against Willem II after making remarks about the captain Roland Alberg. Hansen made his first team return in the last game of the season against PSV Eindhoven, which they lost 3–2. When the season ended, the club hoped to keep Hansen on a longer term. On 11 August 2015, Hansen scored his first ever professional goal, to earn his team a last-minute draw against PSV. As a result, Hansen was named Voetbal International's Player of the Week. On 17 June 2016 he was awarded ADO Den Haag's Goal of the Season Award for the strike.
On 18 June 2016, Hansen joined German Bundesliga side FC Ingolstadt 04 on a four-year-deal. Hansen made his league debut by starting in a 0–2 home defeat by FC Augsburg on 5 November 2016.
