Uber is now the Most Valuable Startup in the World.

Uber is now the most valuable startup in the world. According to CNN Money, the company has closed a new round of funding of nearly $1 billion.t he new funding comes from investors including Microsoft (MSFT, Tech30) and Bennett Coleman & Co., an India media conglomerate. These are new investors to Uber -- or at least newly disclosed investors, according to PrivCo.

PrivCo , a data provider on privately-held companies, this values the firm at close to $51 billion. Uber's valuation has increased by $10 billion in just seven months, said PrivCo research analyst Chris Pisarski. The company had raised $1.8 billion at a $40 billion valuation in just December.

That means it surpasses Chinese smartphone company Xiaomi as the most valuable privately-held company. Xiaomi was most recently valued at $46 billion, according to PrivCo. Airbnb comes in third; it's valued at over $25 billion. 

While it took Facebook (FB, Tech30) nearly seven years to achieve a $50 billion valuation, Uber has hit it in just five years. The service operates in more than 300 cities in 58 countries.

The money will be used to grow its markets in India, where it has committed to investing $1 billion in its operations in the next nine months, as well as in China.

Sources: CNN. Privco