In 2018, she and Pagan's Mind guitarist Jørn Viggo Lofstad premiered their hard rock duo Northward.

[2] Because of the burnout that After Forever bandmate Sander Gommans underwent, the band took a year off starting in January 2008 but ultimately decided to call it quits in February 2009.

[4] ReVamp's first album was produced with After Forever keyboardist Joost van den Broek, bass player Jaap Melman (formerly of Dreadlock Pussy)[5] and guitarist Waldemar Sorychta (Grip Inc., Voodoocult, Eyes of Eden and Despair) as songwriters and producers.

The final line-up of ReVamp featured keyboardist Ruben Wijga, bass player Jaap Melman, guitarists Jord Otto and Arjan Rijnen and drummer Matthias Landes.

In August 2011, Van Canto announced on Facebook, that ReVamp would no longer participate in their Out of the Dark tour, as Jansen suffered a burnout herself.

And everybody in the venue was holding a cell phone, so it would be on YouTube straight away.On 9 October 2013, Nightwish announced Jansen as Olzon's permanent replacement in the band.

[10] In 2015, Nightwish released their first studio album featuring Jansen as the lead vocalist, which was Endless Forms Most Beautiful.

Jansen was the opening act for Metallica in Amsterdam on 29 April 2023 at the last minute, when American heavy metal band Five Finger Death Punch had canceled their appearance that night.

On 9 December 2013, she was also announced as the main vocalist, playing the lead role, for the second full-length album of former Stratovarius guitarist Timo Tolkki's metal opera act Avalon.

On 22 February 2018, Northward, a hard rock project by Jansen and Pagan's Mind guitarist Jørn Viggo Lofstad, was unveiled.

[23][non-primary source needed] In 2019, Jansen participated in the Dutch reality TV show Beste Zangers.

In the last episode she partnered with classical singer Henk Poort to perform "The Phantom of the Opera", which was later released as a single.

It reached number one on the Dutch single charts, and allowed Jansen to go on a sold-out solo tour in the Netherlands.

[35][36] On 18 September 2016, it was announced that Jansen and her husband, Sabaton drummer Hannes Van Dahl, were expecting their first child.

[48][49][50][51] Jansen started studying music at the Dutch Rock Academy in 1999, entering the Conservatorium Tilburg three years later.