Valve has shared some extremely interesting statistics about free-to-play games, confirming that the recent transformation of its popular Team Fortress 2 online shooter into a free-to-play title generated a massive increase in its player count, and a lot of these gamers even started spending money in the title.

Valve's Steam digital distribution service has been used by the company for quite some time to do special experiments and realize just what its users want and how they respond to various strategies.

While it made quite a few products free for certain periods of time, turning Team Fortress 2 into a free-to-play title generated a huge response, at least according to Valve boss Gabe Newell who share his results with GeekWire.

"The most recent thing that also is really puzzling is that we made products available for free on numerous occasions, without significantly impacting the audience size. We recently said, were now going to do something different, were not only going to signal that its free but were going to say, its free to play, which is not really a pricing signal, even though thats what you would ordinarily think it is. And our user base for our first product that we made free to play, Team Fortress 2, increased by a factor of five. That doesnt make sense if youre trying to think of it purely as a pricing phenomenon."

While that jump doesn't mean all that much in terms of profit, Newell also highlights the conversion rates for TF2 players, with a lot of new ones opting to pay money through microtransactions in the game, well above the regular industry average.

"And then the conversion rate, when we talk to partners who do free-to-play, a lot of people see about a 2 to 3 percent conversion rate of the people in their audience who actually buy something, and then with Team Fortress 2, which looks more like Arkham Asylum in terms of the user profile and the content, we see about a 20 to 30 percent conversion rate of people who are playing those games who buy something."

Team Fortress 2 has a thriving MannConomy microtransaction system in place, where players can create their own weapons or items and then sell them for real money to others. This great content offered major incentive to those that wanted to spend some cash on the free game.

Valve is expected to retain the free-to-play model with the upcoming Dota 2, which will see a free open beta stage released soon enough.