Skycalculator

See https://www.skycalculator.com. You can configure workloads (for each VM specify OS, vCPUs/memory/storage) and then it will report cloud costs for:

- AWS

- Azure

- Google 

- vCloud Air

As an example I chose just a single VM: Linux, 2vCPUs, 3.5GB, 200GB storage, on demand price in US$:

Huge difference in pricing between different cloud vendors...Google is very aggressive with their Moore's Law pricing policy and difference will only become greater with time.