A WebSDR is a Software-Defined Radio receiver connected to the internet, allowing many listeners to listen and tune it simultaneously. SDR technology makes it possible that all listeners tune independently, and thus listen to different signals; this is in contrast to the many classical receivers that are already available via the internet. WebSDR servers can register themselves automatically on this site, leading to the below list of currently active WebSDR servers.

Anyone can access any of the SDRs listed on this site and listen in.