This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The FetchEvent.client read-only property returns the Client that the current service worker is controlling.

Note: This feature has been deprecated, with its functionality replaced by FetchEvent.clientId and Clients.get(). See this Github issue for discussion/background.


var myClient = FetchEvent.client;


A Client object.


self.addEventListener('fetch', function(event) {

Browser compatibility

BCD tables only load in the browser

See also