This article applies as of PRTG 25.1.118

Available sensors in PRTG vs sensor usage outside of plan

In the new PRTG web interface, you can find the following card on the home page that contains information about your license usage:



This card shows:

  • The maximum number of sensors that your license allows (your license), which you can see in the top right corner.
  • The remaining number of sensors that you can add within your current license (sensors available), which is the number displayed in the gauge.


Sensors available

Sensors available is the number of licensed sensors minus the number of currently deployed sensors in all states except for the sensors that you have paused.

  • This value is always up to date and reflects your current usage.
  • PRTG counts a new sensor as soon as you create it.

A positive value with a green or yellow gauge shows how many more sensors you can add within your license. A value of 0 means you are currently using your full licensed sensor count.


Sensor usage outside of plan

Sensor usage outside of plan (also called overage) occurs when you use more sensors than your license allows. If this happens, the above mentioned card will instead display the current amount of sensors over your plan with a red gauge. PRTG calculates overage charges via a different method than the live value in the gauge:

  • PRTG counts a sensor as active only after it exists for at least 24 hours and only if you do not pause it within the given day. This means that a new sensor lowers your Sensors available value immediately, but does not count toward overage until it exists for 24 hours. If you delete a short-lived sensor within a day, it does not affect your overage bill.
  • PRTG takes the daily peak of active sensors and averages this peak across the calendar month. Therefore, a spike might not lead to an overage charge.


For the complete overage calculation and the overage charges that may apply, see the Overage Policy on the Paessler Terms and Conditions webpage.


Sensor count in previous PRTG versions

Note: In versions prior to PRTG 25.1.118, the classic PRTG web interface also included a gauge but with different calculation methods. Do not use these older displays to assess your license or overage status. We recommend you to use as of PRTG 25.1.118 for an accurate, real-time view of your sensor usage.

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