Microsoft's cloud competitor to Amazon remains its fastest-growing business by far

Satya Nadella, CEO of Microsoft
Ruben Sprich | Reuters

Microsoft Azure — the company's cloud platform which competes with Amazon's AWS — grew revenue by 93 percent year over year, according to the company's December quarterly earnings report. Azure compute usage more than doubled from last year.

The company did not detail Azure financials in its earnings report, but the annualized revenue run rate for Microsoft's Commercial cloud — which includes Office 365 commercial, Azure, Dynamics 365, and other cloud products — tops $14 billion, Microsoft said in its earnings press release. Run rate measures the amount customers would pay over the course of a year, given current usage rates; the actual annual revenue will probably be higher, if Azure and other cloud services keep growing.

Revenue from its cloud-based productivity software suite for businesses, Office 365 commercial, was the second fastest growing segment, up 47 percent year over year.

Wall Street is particularly focused on how well Microsoft is growing its cloud products, seen as the key to the company's future, and its shares hit a record high in after hours trading.

The company reported second-quarter adjusted earnings per share of 83 cents on revenue of $26.07 billion. Analysts had expected the company to post earnings of 79 cents a share on $25.3 billion in revenue, according to Thomson Reuters consensus estimates.

— With reporting from CNBC's Christine Wang.