LinkedIn claims 70 million users worldwide

LinkedIn claims that a third of all UK professionals are registered on the site

LinkedIn has revealed that its user base has grown to over 70 million worldwide, four million of whom are based in the UK.

The business social networking site said that the number of UK users had shot up in the past nine months by one million, and that one new member joins every second. LinkedIn estimated that a third of all UK professionals are registered on the site.

Kevin Eyres, managing director of LinkedIn Europe, suggested that social networking is increasingly important for professionals as it is becoming the accepted way to represent themselves as an individual.

"UK professionals from all industries are adopting LinkedIn with accelerating speed. Driving this growth is the increasing realisation that an online professional profile is the best way to present yourself publicly because of the opportunities that come your way," he said.

"In our working lives, the internet is now often our first destination when we're looking for advice or expertise, and it makes sense to have your skills and experience available and up to date so you can be discovered by your next opportunity."

LinkedIn claimed that a quarter of companies in the UK FTSE 100, and 50 per cent of Fortune 100 companies, now make hires through the site, and that one billion people searches have been carried out on LinkedIn in the past 12 months.

However, the firm has been criticised by security experts for allowing hackers to mine useful corporate information which could be used to launch targeted attacks.