Globally AWS is the clear market leader for cloud infrastructure services (IaaS), reporting a staggering $40 billion annual run rate for 2019. By way of comparison, Google Cloud parent company Alphabet broke out its annual figures for the first time in 2019, reporting a $10 billion run rate for the cloud division for the year. This does include revenue driven by cloud software-as-a-service (SaaS) like G Suite, however.
Microsoft doesn't break out its numbers as neatly but Azure is part of its Intelligent Cloud group, alongside SaaS versions of Office and Dynamics software, which accounted for nearly $12.5 billion for Q2 2020 alone, so an annual run rate of $50 billion.
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