Photo via Twins or Not?
Photo via Twins or Not?

Building off the viral success of its guess-your-age tool, Microsoft has now launched Twins or Not?

Twins or Not? is the follow-up to How-old.net, a site that MS engineers built about a month ago to “experiment about ‘observing virality in real time.’ ” Microsoft’s Mat Velloso details the build of Twins or Not? on his blog here, and says it took just four hours.

To have some Friday fun with the new one, we’ve thrown in some well-known faces, courtesy of Wikipedia, just to see how accurate Twins or Not? can be:

First up, Microsoft’s very own co-founders, Bill Gates and Paul Allen:

Photo via Twins or Not?

How about GeekWire’s John Cook and Todd Bishop?

Photo via Twins or Not?

Young Woz vs. older Woz?

Photo via Twins or Not?

It seems to be right on the money with real twins, aka Olsen and Winklevoss:

Photo Twins or Not?

Screen Shot 2015-06-05 at 11.20.08 AM

How about NBA superstars LeBron James and Stephen Curry?

Screen Shot 2015-06-05 at 11.16.02 AM

Now, go wild. The possibilities are endless.

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