StorageManager: persisted() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since December 2021.

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Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

Note: This feature is available in Web Workers.

The persisted() method of the StorageManager interface returns a Promise that resolves to true if your site's storage bucket is persistent.

Syntax

js
persisted()

Parameters

None.

Return value

A Promise that resolves to a Boolean.

Exceptions

TypeError

Thrown if obtaining a local storage shelf failed. For example, if the current origin is an opaque origin or if the user has disabled storage.

Example

js
if (navigator.storage && navigator.storage.persist) {
  navigator.storage.persisted().then((persistent) => {
    if (persistent) {
      console.log("Storage will not be cleared except by explicit user action");
    } else {
      console.log("Storage may be cleared by the UA under storage pressure.");
    }
  });
}

Specifications

Specification
Storage
# dom-storagemanager-persisted

Browser compatibility