UsVsTh3m, the Daily Mirror publisher's Buzzfeed-style social content website, has more than doubled its traffic in a month, hitting 7 million unique users in November.

Trinity Mirror said that the massive boost – the site hit 3 million unique users in October – was fuelled by catchy content such as the North-o-Meter, an "uncannily accurate online measuring tool" that tests "how northern" users are.

More than 3.8 million people have so far played the game; at one point 20,000 were playing at the same time.

The publisher said that the "digital humour and entertainment" brand, which soft launched at the end of May, topped 1 million monthly users for the first time in September.

Of the 7 million unique users to visit last month, 57% accessed the site from mobiles or tablets and 43% from desktops.

Seven in 10 users accessed UsVsTh3m from the UK with the average time on the site of 6 minutes.

Only 2% of traffic came from search engines, showing the power of social media and recommendation in driving the site's growth.

70% of visits were from the UK. The average time on the site was six minutes. Just 2% of the traffic came from search engines.

"This is an amazing achievement by the team to have grown so quickly in such a short space of time and shows the importance of experimentation for publishers," said Trinity Mirror digital product developer Malcolm Coles. "Our next experiment, Ampp3d, producing socially shareable data journalism launches shortly."

Ampp3d is expected to launch later this week.

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