Google's share of the US search market declined one per cent during July, ending the firm's 11-month run of consecutive gains.

According to tracking and analysis company ComScore Networks, Google sites maintained their lead on the pack with 2.7 billion search queries, or 43.7 per cent of all searches performed during the month.

Yahoo recorded 1.8 billion, after the company posted modest market share gains for the second consecutive month to reach 28.8 per cent of US searches.

MSN Microsoft followed in third place with 802 million searches, holding steady with 12.8 per cent share.

Time-Warner Network took 5.9 per cent of the market, or 366 million searches, and Ask Network recorded 5.4 per cent or 338 million. Each showed modest market share gains compared with the previous month.

Americans conducted 6.3 billion searches online in July, according to ComScore, down two per cent compared with last month and reflecting seasonal declines typically seen in July.