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.
More background information is available here.
Questions and comments can be sent to PA3FWM,
the author of the WebSDR software and maintainer of this site;
but please check the frequently asked questions first.
WebSDR servers can register themselves automatically on this site,
leading to the below list of currently active WebSDR servers.
Since April 2018, the Chrome browser is reluctant to play audio on WebSDR sites.
If you use Chrome and have no audio on WebSDR sites,
a workaround is to switch off Chrome's new autoplay policy, by typing
chrome://flags/#autoplay-policy in the navigation bar
and changing this setting from Default to No user gesture is required
(and restarting the browser).
Currently there are - servers active, with - users and - MHz of radio spectrum.
and covering MHz.
Note: the locations on the map are only accurate to a few km,
because they are derived from the QTH locators.