Career
Janssen played in the B-Youth for her home club, RKSV Wittenhorst, and in the summer of 2013, joined Société Générale de Surveillance Essen in the German Bundesliga. She turned down offers from BeNe League teams PSV/Football Club Eindhoven and AFC Ajax. On September 8, 2013 (1st Round), she debuted in the 3:3 draw against BV Cloppenburg in the Bundesliga.
She signed for Arsenal Ladies in 2015.
Janssen played for the first time for a Junior selection of Royal Dutch Football Association on 17 March 2010 at the friendly match of U-15 national team against England. In 2012 she was captain of the Dutch U-17 team in the qualifying matches for the 2012 Union of European Football Associations Women"s Under-17 Championship and also led the team, as captain, in qualifying for the 2013 Union of European Football Associations Women"s Under-19 Championship.
Janssen played all five matches in the tournament. In 2014, she was called for the senior team for the first time, taking part in the Netherlands squad for the 2014 Cyprus Cup.
On March 5, 2014 she made her debut, when she came off the bench in the 65th minute at 2:2 against Australia.