She began her modelling career in 2003, in the Netherlands and was quickly sent by her agency to New York where she was cast by lingerie brand Victoria’s Secret.

[15] In July 2007, earning at an estimated total of $1.5 million in the previous twelve months, Forbes named Kroes fourteenth in the list of the world's 15 Top-Earning Supermodels.

[23] From November 2009 to July 2010, Kroes wrote a monthly column about her life for the Dutch edition of Marie Claire.

[24] In February 2010, Kroes returned to the catwalk during fashion week for Prada with fellow Angels Alessandra Ambrosio and Miranda Kerr.

Prada was praised by former editor-in-chief of Glamour, Cosmopolitan and Marie Claire magazines, Bonnie Fuller in her blog for using a curvy model such as Kroes for the fashion show.

[7][26] In 2014, Kroes appeared in the new Calvin Klein Reveal Fragrance commercial alongside Charlie Hunnam, as well as continuing her long-standing contracts.

[29] Kroes is actively involved with the non-profit organization Dance4Life, which uses song and dance to educate youth about HIV and AIDS prevention.

[40][41] In September 2021, Kroes elicited some controversy by revealing her anti-vaccine point of view on Instagram, stating she would "not be forced to take the shot", in reference to the COVID-19 vaccine.

[42][43] In November 2021, Kroes shared a video on her Instagram account stating that COVID-19 vaccines are part of a plot by "satanists" to "reduce the global population".

[44] Kroes, whose net worth is estimated by Quote at €29 million, has also been criticised for applying for government compensation of loss of income due to COVID-19 while at the same time spreading misinformation about the pandemic.