Streaming platforms estimate Unique Listeners using technical identifiers generated by devices and playback sessions.
When the same listener uses multiple devices, such as:
- A mobile app,
- A web player,
- A smart speaker,
- A connected car,
each device may generate different identifiers and appear as separate listening activity within reporting systems.
For example, a listener may:
- Listen on a work computer during the day
- Continue listening on their phone while travelling
- Use a smart speaker at home later that evening
Depending on the platforms involved and the listener identification available, reporting systems may interpret this as multiple distinct listeners rather than one individual moving between devices.
Radar makes use of a listener IP and User Agent combination if a unique session ID is not available.
Modern apps and players increasingly use listener IDs and improved session identification to reduce duplicate counting where possible. However, no streaming platform can perfectly recognise the same person across every device and listening environment.
This is one of the reasons Unique Listener reporting should generally be treated as an estimate rather than an exact audience count.
For more information, see: Why Unique Listeners Are an Estimate, Not an Exact Audience Count Understanding Digital Radio Metrics