How Long it Took the Richest People to Become Billionaires by Business Insider

The richest people in the world found success at various ages.
Warren Buffett spent over 25 years as a millionaire before becoming a billionaire, while it took Mark Zuckerberg and Jeff Bezos less than two years to graduate to billionaire status.
The richest people in tech averaged five years as millionaires before becoming billionaires. This graphic shows how long it took the richest people in the world to go from millionaire to billionaire.