When using Azure you can reduce Virtual Machine costs by either using a Reservation or only turning the VM on when it is needed, for example during business hours. There's a threshold at which it's cheaper to leave the VM running 24/7 and switch to a reservation and this chart helps illustrate that.
The Virtual Machine pricing and Reserved Instance discount varies between Azure Regions and VM sizes, this chart pulls current data from the Azure pricing API based on the choices made above.
Example: A D2v3 VM in UK South running Mon-Fri 8am-6pm is on for 40 hours a week. It is cheaper to run this without a reservation. If the same VM is run 8am-8pm 7 days a week that's 84 hours, and the weekly cost of a 3-year Reserved Instance is lower.
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