# Licensing Models ## Perpetual licensing model It refers to licenses which have no subscription interval or expiration date set. A user buys a license and can use your product for lifetime without any need of paying again. ## Metered licensing models ### Subscriptions Licenses can be metered by time and they would expire after a certain amount of time period. Your customers would usually pay a monthly or a yearly subscription fees and when they renew, the license should also be renewed. ### Meter by usage Sometimes you want your customers to pay for what is actively used regardless of how long they possess your product. The usage can be defined as the amount of time for which your app is used, number of times it is run, number of specific operations etc. depending on your business requirements. ## Seat based licensing models ### Node locked licenses A node locked license is bound to a machine on which the license was activated. It means that the license key cannot be used on any other machine (if license allows a single activation/seat). If license allows multiple activations (multi-seat), then after all the activations are used, the license key cannot be used on other machines. ### Floating licenses A floating license is temporarily bound to a machine for a specific amount of time. When the time expires the activation (seat) is automatically freed up (if not renewed), so that any other machine can use the license. So if your floating license allows for 100 activations (seats), then at any instant of time no more than 100 machines can use your application. ## Which licensing model should I choose? You will most of the time use node locked licenses which would be either perpetual or subscription based. When licensing your product to any university or a big company which may require large number of license seats, you will usually opt for floating licenses as that is more economical for your customers. Other than this you can add some other restrictions too like usage count or implement a completely custom licensing model using metadata fields which you can add to your licenses. ## Need help In case you need help for implementing any of the above mentioned licensing models, we'll be glad to help you. You can either post your questions on our [support forum](https://forums.cryptlex.com) or can contact us through [email](mailto:support@cryptlex.com). --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.cryptlex.com/getting-started/licensing-models.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.