Google's revenue grew to $5.19bn (£2.6bn) during the first quarter, a 42 per cent rise on the $3.66bn (£1.83bn) reported after the first three months of 2007.

Net income at the search giant jumped to $1.31bn (£656m), up from a flat $1bn (£501m) in the first quarter of last year.

Google's $3.1bn (£1.6bn) purchase of advertising firm DoubleClick had minimal impact on its earnings, the company said. The acquisition was announced in April 2007 and was finally completed last month.

"Our ongoing innovation in search, ads, and apps helped drive healthy growth globally across our product lines, yielding another strong quarter for Google," said Google chief executive Eric Schmidt.

"As we integrate DoubleClick into our advertising platform, we see exciting new ways to improve the user experience and increase value for our advertisers and partners. Also, while exercising operational discipline, we continue to explore opportunities that add value to users everywhere and to Google in the long term."

Meanwhile the financial intelligence firm ComScore saw its value drop eight per cent in after-hours trading yesterday, following discrepancies between its predictions and Google's final results.

ComScore forecast that the number of users clicking on Google's advertising links would rise a measly 1.8 per cent from the rate reported last year. But the search giant's actual results showed an annual increase of 20 per cent.