SpaceX the Alan Notes

Musk standing in front of a Tesla Model S. Source: Maurizio Pesce via Wikimedia Commons.

What is Elon Musk's net worth? And where did it come from?

Elon Musk has an estimated net worth of $13.2 billion, making him the 87th richest person in the world, according to ' real-time ranking on June 15. Microsoft founder Bill Gates currently reigns as the wealthiest person on this planet, with a net worth of $79.1 billion.

Forbes doesn't break down the sources of Musk's net worth, but we're going to pop the hood and look at the components of the serial entrepreneur's wealth by digging into his filings with the Security and Exchange Commission. The bulk of the 43-year-old's net worth consists of the stock he owns in three companies he founded or co-founded: Tesla Motors , SpaceX, and SolarCity .

Musk's net worth is accelerating as fast as a Tesla Model S
Musk's net worth has been on turbocharge thanks largely to the soaring stock price of the electric-vehicle maker he co-founded and steers as CEO and chief product architect. His net worth clocked in at $11.9 billion this February, up from $8.4 billion in February 2014, and $2.7 billion in February 2013, according to Forbes.

Tesla's stock has soared more than 1, 400% from its IPO price of $17 per share in June 2010 to its current (as of June 15) price of $250. That's taken Musk's net worth on a joyride, as the South African native owns a 26.7% stake of the $31.7-billion market-cap company, according to SEC filings. Thus, Tesla accounts for about $8.5 billion of Musk's net worth.

Musk's wealth skyrocketing with SpaceX

CRS-6 cargo resupply mission to International Space Station for NASA in April 2015. SpaceX's Falcon 9 rocket launched the Dragon spacecraft. Source: SpaceX.