The firm claims this is now the UK's largest online audience segmentation and targeting service and has been achieved after gaining access to ISP data about users.
The increase in the sample means a boost in the number of websites that can be analysed, according to Hitwise marketing manager Jannie Cahill, with 150,000 sites now involved in the basic demographic analysis and 70,000 sites involved in the more detailed lifestyle demographic search.
Simon Chamberlain, Hitwise UK general manager, said: "This latest innovation means that companies both big and small can better understand their online audience as well as that of their competitors, in order to make more informed online media and partnership decisions."
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