Web Side Story made the claim in a survey of European users during June, using stats based on its HBX Analytics software.
Firefox is used by one in 10 US users, the firm claimed.
Web Side Story analyst Geoff Johnston said: "Germans have always seemed to embrace alternatives to Microsoft when it comes to web browsers. Firefox appears to have a stronger foothold in some European countries than in the US. Most of these gains appear to have come at the expense of Microsoft."
| Country | Internet E | Firefox | Others* | Daily Sample |
| Germany | 65.04% | 26.8% | 8.16% | 2,181,802 |
| France | 82.27% | 14.89% | 2.84% | 1,053,701 |
| Italy | 84.76% | 12.46% | 2.78% | 678,166 |
| Spain | 88.12% | 9.86% | 2.02% | 767,382 |
| UK | 88.78% | 8.82% | 2.40% | 6,537,577 |
| USA | 84.64% | 9.95% | 3.45% | 49,732,535 |
Web Side Story said browser usage share is the percentage of visitors from a country using one browser over another. The sample size is 80 million Internet users a day. µ