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

This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The persisted property of the StorageManager interface returns a Promise that resolves to true if box mode is persistent for your site's storage.

Syntax { ... })




A Promise that resolves to a Boolean.


if ( && {
    if (persistent)
      console.log("Storage will not be cleared except by explicit user action");
      console.log("Storage may be cleared by the UA under storage pressure.");


Specification Status Comment
The definition of 'persisted' in that specification.
Living Standard Initial definition.

Browser Compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 55.0 57 (57) ? 42 ?
Feature Android Android Webview Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support No support 55.0 No support ? 42 ? 55.0

Document Tags and Contributors

Contributors to this page: chrisdavidmills, YourDoge, shawn_huang, david_ross, jpmedley
Last updated by: chrisdavidmills,