in the tool you need to input the number of hosts you have, the amount of CPU's in each host and cores per CPU. Then enter the number of VMs you need, and input the license cost of Datacenter v Standard provided by your licensing partner. Example below:
You can use either license with VMware. A Datacenter licence entitles you to run unlimted VMs, and based on the amount of VMs you are running, you'll need to work out if its more cost effective to purchase Datacenter or Standard licences.
The VMware licensing is a separate piece - I "think" you can run up to 10 VMs for free on a single host without licencing VMware, but you would need to check that with them directly.
Hope this helps,
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