Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

The SyncEvent interface represents a sync action that is dispatched on the ServiceWorkerGlobalScope of a ServiceWorker.

This interface inherits from the ExtendableEvent interface.

Event ExtendableEvent SyncEvent



Creates a new SyncEvent object.


Inherits properties from its ancestor, Event.

SyncEvent.tag Read only

Returns the developer-defined identifier for this SyncEvent.

SyncEvent.lastChance Read only

Returns true if the user agent will not make further synchronization attempts after the current attempt.


Inherits methods from its parent, ExtendableEvent.


Browser compatibility

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