The site will be modelled on IPC owner Time Warner's US website, www.instyle.com, which attracts 1.8 million unique users and generates 30 million page impressions per month.
The US site features exclusive celebrity coverage including gossip from parties and fashion shows, celebrity blogs, videos, newsletters and behind-the-scenes photo shoots.
IPC has yet to establish a web address for the site, but the options include www.instyle.co.uk or re-routing British visitors to www.instyle.com to the UK version.
Kirsten Price, InStyle's publishing director, said that, as with the magazine, the site would use relevant US content as well as generating exclusive UK coverage.
IPC is hiring a dedicated editorial team for the site, including a web editor.
The launch comes five years after Time Warner adapted the US magazine for the UK market. The UK edition's last ABC was 197,031.
IPC chief executive Sylvia Auton would not be drawn on the other titles set for online development.
Woman & Home, Essentials, What's On TV and IPC's traditional women's weeklies including Chat and Woman are among the publisher's key titles without websites, while Pick Me Up and TV Times have only basic online offerings.
Auton said digital would account for most of IPC's launch and relaunch activity in 2007 and that the publisher was seeking to exploit its ties with Time Warner stable-mate AOL more effectively.
In the past year, IPC has appointed digital directors for each of its divisions and promoted Neil Robinson, publishing director of its TV titles, to the new role of digital development director across the company.