She said: "Karl your genius touched the lives of so many, especially Gianni and I. We will never forget your incredible talent and endless inspiration. We were always learning from you."
Model Alexa Chung recalled how "witty and generous" Lagerfeld was when she interviewed him, and said knowing him was "an honour".
She wrote: "Rest in peace, Karl. I remember being so scared to interview you and yet you were in fact incredibly witty and generous.
"Thank you for inviting me to some of the most glamorous experiences of my life, it was an honour to know you. Oh yeah and thanks for the dry shampoo tip, will always think of you as I powder my wig."
Also amongst the stars paying their respects after the tragic news broke was Kris Jenner, who described the fashion icon as a "dear friend".
She tweeted: "It was such a thrill and a pleasure to have met you, to have worked with you, and to have experienced the amazing times when you would photograph my girls for your beautiful campaigns.
"There will never be another like you, my dear friend. You will be truly missed."
The outpouring of emotion comes after a Chanel spokesperson confirmed the news in a statement.
They said: "It is with deep sadness that the House of Chanel announces the passing of Karl Lagerfeld, the Creative Director for the Chanel Fashion House since 1983.
"An extraordinary individual, Karl Lagerfeld, reinvented the brand's codes created by Gabrielle Chanel."
