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 readAsText() method of the IDBFileHandle interface reads the content of the associated file and provide the result of that reading as a string. In many ways, it performs like the FileReader.readAsText() method.

The reading operation starts at the position given by the location property.


readAsText(size, encoding)



A number representing the number of bytes to read in the file.

encoding Optional

A string indicating the encoding to use for the returned data. By default, UTF-8 is assumed if this parameter is not specified.

Return value

An IDBFileRequest object to handle the success or failure of the operation. In case of success, the request's result is a string representing the data that have been read.


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

Browser compatibility

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

See also