Core licensing is one of the most confusing parts of buying Windows Server or SQL Server. The rules around minimums, per-processor counts, and 2-core packs trip up even experienced IT buyers. Use the calculator below to get a quick estimate of how many core licenses you need, then check it with our team before you order.
Core Licensing Calculator
Work out how many core licenses you need for Windows Server 2025 or SQL Server 2025. Estimate only, confirm with us before you buy.
How Windows Server 2025 core licensing works
Windows Server 2025 is licensed by physical core. You license all the physical cores in the server, with two minimums: at least 8 cores per physical processor, and at least 16 cores per server. Licenses come in 2-core and 16-core packs. Standard edition covers up to 2 virtual machines per fully licensed server, while Datacenter allows unlimited virtual machines. If you are activating several servers, see our guide on activating a Windows Server 2025 KMS host key.
How SQL Server 2025 core licensing works
SQL Server 2025 per-core licensing covers all the cores available to the SQL instance, with a 4-core minimum, sold in 2-core packs. Per-core suits internet-facing or large user-base workloads. If you have a small, countable set of users, the Server plus CAL model can work out cheaper. Our SQL Server 2025 licensing guide breaks down Standard vs Enterprise and per-core vs Server plus CAL.
Need a hand?
This calculator gives an estimate based on Microsoft’s standard core-licensing rules. Edge cases like virtualisation density, failover rights, and high availability can change what you need. Send us your setup and we will confirm the exact licenses, then supply them with instant delivery and activation support.
