Wed Apr 29, 2015 6:30pm EDT San Francisco

Microsoft Corp is targeting $20 billion in annual revenue from its cloud-computing businesses by the end of fiscal 2018, Chief Executive Satya Nadella said on Wednesday, signaling a tripling of such revenue in three years.

The world's largest software company is one of the leaders in the cloud, essentially providing computing power and storage to customers through its network of data centers.

Microsoft said last week that its total commercial cloud revenue, which includes online versions of its Office and Dynamics applications, is running at $6.3 billion per year.

Its closest rival in the cloud, Amazon.com Inc, said last week its competing Amazon Web Services operation took in $1.57 billion in revenue in the quarter, which would also equal an annual rate of $6.3 billion.