User CAL or Device CAL: which access license you need
Two calculation examples show which access license wins when. Also, the option to mix both types, which hardly anyone uses in practice, even though it is often the most economical.
On this page
Short answer: A User CAL is tied to a person, allowing them to access from any number of devices. A Device CAL is tied to a device, allowing any number of people to access through it. The decision rule is: count people, count devices, license the smaller number.
Why there are two variants at all
Microsoft sells the server license and the access right separately. The server license allows the software to run on the hardware. It does not allow anyone to work with it. That's what the access license is for, in English Client Access License, or CAL for short.
Because businesses operate very differently, the CAL comes in two versions. Both cost a similar amount, but cover different things.
The two variants in plain text
User CAL
It belongs to one person. This person may access the server from a desktop, laptop, tablet, and phone without incurring further licenses.
Device CAL
It belongs to one device. Whoever logs on to this computer is covered. It doesn't matter whether one person works there or twenty in succession.
Two practical examples
Example office. An accounting firm employs ten people. Each has a desktop computer, and four also have a laptop for external appointments. That's ten users and fourteen devices. With User CALs, you need ten licenses; with Device CALs, fourteen. The User CAL wins.
Example shift work. A production runs with twenty employees in three shifts at six terminals in the hall. That's twenty users and six devices. With Device CALs, you need six licenses instead of twenty. The Device CAL wins, and significantly.
The rule behind it is always the same, no matter how big the company: The smaller of the two numbers determines which type you buy.
The point almost no one knows
You are allowed to mix both types in the same network. This is stated in the licensing terms and is used far too rarely in practice.
Consider a craft business: In the office, three people work at three computers and a shared laptop. In the workshop, eight mechanics share two terminals. Calculated cleanly, you take three User CALs for the office and two Device CALs for the workshop, making five instead of the eleven that a uniform solution would cost.
"We had bought User CALs for all employees - but the shared terminals in the workshop with Device CALs would have easily cost half." An IT service provider describes how he was able to significantly reduce costs for a customer by mixing both license types.
What is often forgotten
- Access is more than logging in. Even those who only access a file share or a network printer on the server need a CAL.
- Even a single person needs one. There is no exemption limit.
- External users count. Service providers with server access also need a license.
- CALs must not be older than the server. Newer CALs, however, cover older servers.
Calculate it briefly
If you want to know what your setup specifically needs, use the CAL configurator. Three questions, and you'll get the exact combination including quantity and price.
You can find the appropriate licenses under Access Licenses, and the servers themselves under Windows Server. All further basics are explained in the Server Guide.
