Microsoft recently created a neat little tool that attempts to guess your age and gender based solely on a photo. Originally designed to test the company’s newly released face detection APIs and sent out to just a few hundred people, the page quickly went viral with more than 35,000 people having tried it out after just three hours.

To try it for yourself, simply visit how-old.net and upload an image of yourself (or find and upload a photo of someone else online).

The tool was built by a couple of developers in just one day and demonstrates the power of machine learning. It’s not always accurate – it guessed Mark Zuckerberg’s age as 36 when in reality, he’s just 30 – but it was just one year off with a guess of 90 for Hugh Hefner (he’s 89). I tried tricking it with a photo of a cute koala but the tool didn't fall for it.

The release coincides with Microsoft’s ongoing Build conference which got under way on Wednesday and runs through today in San Francisco. 

Found is a TechSpot feature where we share clever, funny or otherwise interesting stuff from around the web.