Deprecated: 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.

Note: The three non-standard interfaces IDBMutableFile, IDBFileHandle, and IDBFileRequest are disabled by default. Consider using the File and Directory Entries API instead.

The location property of the IDBFileHandle is a zero-based index representing the position of the read/write pointer within the file. Its value indicates at which bytes within the file any write or read operation will start.

This value is changed automatically after every read and write operation. The special value null means end-of-file.

This property can be changed at will.


A number or the null value, meaning end-of-file.


This feature is not part of any current specification. It is no longer on track to become a standard.

Browser compatibility

This property is not supported by any current browser. From Firefox 102 it is behind the preference dom.fileHandle.enabled.

See also