UK-based GWI, which surveys consumers to aid advertisers, has raised $180 million from private equity firm Permira Growth Capital at a valuation of $850 million.

Founded in 2009, GWI has tripled revenues since raising $40 million in its first funding round from U.S. growth fund Stripes in 2018.

"We collect millions of responses to our surveys a year and provide hundreds of millions of data points," Chief Executive Officer Tom Smith said in an interview, adding a customer like Google could use this data to engage advertisers.

GWI is looking to use machine learning and language processing to provide audience intelligence that is easy to understand and insights could be obtained as easily as a Google search result.

Smith plans to take the company public in the next few years.

(Reporting by Supantha Mukherjee, European Technology & Telecoms Correspondent, based in Stockholm; Editing by Mark Potter)