The redesign, overseen by Stuart Selner, Marie Claire's creative director, aims to deliver a glossier, cleaner look and to provide easy navigation though the range of content.
The includes an expanded news offering, with fashion, celebrity, health and world stories, to which visitors can add comments.
The lifestyle section includes features on ethical living, restaurant reviews and Buy of the Day.
Blogs, forums and competitions can be found in the community section, while improved photo galleries deliver coverage of the major fashion shows and a red carpet gallery, which is updated daily.
Marie Claire aims to satisfy its advertisers, as well as its readers, with the redesign by providing new display formats and promotional opportunities that work across the magazine and website.
Carla Bevan, marieclaire.co.uk editor, said: "The new site is more expansive, more interactive, bolder and brighter than its predecessor and we hope our readers and advertisers are as pleased with it as we are."
Richard Johnstone, Marie Claire publishing director, said: "Satisfying the growing demands of advertisers online is a key focus for us so the new site not only offers new display formats, including leader boards and prominent 300x600 double skies, but there are also more tailor-made promotional opportunities that work seamlessly across both the magazine and website."