Sony Online Entertainment's free-to-play MMO Free Realms has notched up over two million unique users since launching a month ago.
According to the developer, 75 per cent of users are under 17 years of age, with 46 per cent under 13. Nearly a third of all players are female.
"In less than a month, Free Realms has captivated a core player base of tween and teen gamers, while also strongly resonating with MMO gamers," commented John Smedley, president of Sony Online Entertainment.
"We wanted to create a game to play with our families and are excited to have hit the mark with our intended audience."
Although free-to-play, users can buy Station Cash game cards from Best Buy, Blockbuster, Rite Aid, 7-Eleven and Target to upgrade to Membership status and buy in-game items for the game.