The Most Successful Startup Founders Are This Age, Study Finds (And No, It's Not Early 20s) Despite the success of entrepreneurs like Bill Gates and Steve Jobs, who were both in their early 20s when they started now wildly successful companies, research finds that those stories are the exception, not the norm.

We've all heard the stories of how Bill Gates and Paul Allen were just 20 and 22, respectively, when they founded Microsoft in 1975. Jeff Bezos was 30 when he founded Amazon. Steve Jobs was just 21 when he founded Apple.

The success stories of young startup founders have in some ways given the impression that youth is tied to success in Silicon Valley. However, new research from Harvard Business Review found that this is mostly a myth, and if given a choice to bet on a young entrepreneur or a middle-aged one, you're safer betting on the latter.

Using confidential administrative data sets from the U.S. Census Bureau, the team of HBR researchers found that the average age of entrepreneurs at the time of their company's founding is 42.

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To narrow the data from those businesses to fit a more stereotypical high-tech startup in the vein of Apple, Amazon or Microsoft, the researchers used factors such as if the firm was granted a patent, received VC investment or operated in an industry that employs a high number of STEM workers. To take it a step further, the researchers zeroed in on the most successful startups (top 0.1% based on growth in the first five years).

HBR found that the average startup founder who fits the aforementioned data set was 45 when they started their company.

Among the factors that might explain why older entrepreneurs could have an advantage over younger founders is work experience, which HBR noted plays a crucial role in success. The researchers found that those who had at least three years of work experience before founding their company were 85% more likely to launch a successful startup.

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HBR further debunked the myth of the 20-something startup founder by looking more closely at Bezos, Jobs and Gates' stories. Although they founded their companies early, it wasn't until much later that they experienced the booming success we see today. Bezos was 35 when Amazon began selling more than books, expanding its business tremendously, and he was 41 when Amazon Prime launched. Similarly, by the time Apple released what would become its most profitable innovation, the iPhone, Jobs was 52. And although Bill Gates was the youngest billionaire at 31 in 1987, that didn't happen until more than 10 years after Microsoft's founding.

Maybe the adage rings true: Wisdom really does come with age.

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