Elon Musk AP Photo/Mark J. Terrill Elon Musk's rocket company SpaceX is now worth $12 billion, The Wall Street Journal reports, based on details of its latest $1 billion funding round.

SpaceX raised the money from Google and Fidelity, but The WSJ's sources say the majority of the cash came from Google.

The search giant, which is interested in SpaceX's ambitions of using satellites to beam low-cost internet around the world, reportedly bought a 7.5% stake for $900 million.

That would bring SpaceX's valuation to a sky-high $12 billion, ranking it fourth on The WSJ's list of billion-dollar private companies.

It's now more valuable than Dropbox, Snapchat and Airbnb, but still behind Xiaomi ($46 billion), Uber ($41.2 billion), and Palantir ($15 billion).