All Black USB licenses (numbers 22000–40999) are perpetual. Newer red or green USB keys and softkey licenses can be either perpetual or subscription. 2. Single-User Fixed Licenses

Historically, many users preferred , which allow the software to run indefinitely. However, since being acquired by Ansys, the licensing landscape has shifted significantly.

Modern softkey licenses generally require an internet connection for periodic validation, though network licenses can often be "borrowed" for offline use for up to 30 days.

These are leased for a set duration (typically 6 months to 3 years). Once the term ends, the software will no longer run until renewed.

Navigating the Modern Landscape of Zemax OpticStudio Licensing

For those moving to the current subscription model, OpticStudio is organized into three distinct tiers to match different engineering needs:

Managing your license now primarily happens through the or the Ansys Licensing Client Settings .

These are owned outright. While they run the software forever, they require an active support agreement to access new releases or technical support.