Short answer: it depends. Nobody tells you the answer until you actually address to some cloud provider, ask their prices and compare. First of all, you should understand that the cloud provides you a virtual computer. You should be responsible for the costs of all software you install, at least if you use an individual cloud service (private cloud
Therefore, you cannot save on the cost of software per se. You can only improve situation to make your software more busy or by distributing the ownership costs between more people or parties. In my opinion, you can make savings only if you want to provide services (in the most wide sense of this word) requiring intensive use of internet and considerable service power. Usually it happens when you use service models like Infrastructure as a Service, Platform as a Service, Software as a Service. Also, you can make it more cost-effective using, say, community or hybrid cloud solutions.
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