Tina Brown has announced she is leaving the online news magazine The Daily Beast.

Former Vanity Fair editor Tina Brown, who founded the site in 2008 with Barry Diller, said she would focus on a conference business, in particular her annual Women in the World summit.

Tina Brown will leave the site when her contract expires at the end of this year.

Her tenure at The Daily Beast was marked by the website’s unsuccessful merger with Newsweek in 2010.

Tina Brown and her team struggled to turn around the storied print magazine, and advertising revenue continued to plunge as circulation lagged.

She defended her attempt to revive Newsweek, saying she was proud of “the battle we waged to save it from the overwhelming forces of media change”.

Newsweek was sold to IBT Media in August after ceasing publication of its print edition.

Tina Brown has announced she is leaving the online news magazine The Daily Beast.

Tina Brown’s new venture, Tina Brown Live Media, will continue her successful yearly conference, Women in the World, launched in 2010. Luminaries such as Oprah Winfrey and Hillary Clinton have attended in the past.

She co-founded The Daily Beast in October 2008 with Barry Diller after a successful track record running print magazines in the US and the UK.

At age 25 Tina Brown was editor-in-chief of UK society magazine Tatler. She then went on to be the first female editor of The New Yorker magazine, and edit Vanity Fair and the short-lived Talk magazine.

Named after the fictional newspaper in Evelyn Waugh’s satirical novel Scoop, The Daily Beast aimed to prove that online news could be made profitable.

The site was backed by Barry Diller’s IAC/InterActivCorp, which also owns properties such as the dating websites Match.com and OkCupid and other websites such Ask.com and Dictionary.com.

Although the Daily Beast has reported strong web traffic numbers – with an audience of between six million and 16 million monthly visitors – it has had difficulty generating meaningful ad revenue.

The November 2010 merger with Newsweek – which had been purchased by audio magnate Sidney Harman for $1 from the Washington Post Company – added more pressure.

After struggling to contain losses and generate buzz, Tina Brown announced that the venerable magazine would cease print publication on 31 December 2012.

Barry Diller later called the Newsweek acquisition “a mistake”.

IAC will continue to operate The Daily Beast, according to an article posted on the site.

It will be run by executive editor John Avlon and managing editor Deidre Depke.