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

This page is not complete.

The StorageEstimate dictionary is used by the StorageManager to provide estimates of the size of a Web site's or application's data store and how much of it is in use. The method returns an object that conforms to this dictionary when its Promise is resolved.

These values are only estimates for several reasons, including performance and to prevent storage capacity data from being used for fingerprinting purposes. See the individual property pages for details.


This dictionary currently always has both of the following properties defined.

quota Secure context
A numeric value which provides a conservative approximation of how much total storage the user's device or computer has available for use by the site origin or Web app. It's possible that there's more than this amount of space available but you can't rely on that being the case.
usage Secure context
A numeric value approximating the amount of storage space currently being used by the site or Web app, out of the available space as indicated by quota.

See also

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 Contributors to this page: chrisdavidmills, Sheppy
 Last updated by: chrisdavidmills,