Her clients include Adèle Exarchopoulos, Bérénice Bejo, and Valeria Bruni-Tedeschi.
[3] Seydoux is the elder of two sisters born to businessman Henri Jerome Seydoux-Fornier de Clausonne and philanthropist Valérie Schlumberger.
On her paternal side she is the granddaughter of Pathé owner Jérôme Seydoux.
In 2012 she styled her sister for the premiere of Farewell, My Queen at the 62nd Berlin International Film Festival and began to receive requests to officially work as a stylist.
[7] In 2016 Seydoux collaborated with Roger Vivier to create a denim capsule collection inspired by actress Jane Birkin.