The FileReader.readyState property provides the current state of the reading operation a FileReader is in. A FileReader exists in one of the following states:

Value State Description
0 EMPTY Reader has been created. None of the read methods called yet.
1 LOADING A read method has been called.
2 DONE The operation is complete.
The FileReader has been created, but no readAs method was called yet.
A readAs method was invoked. A File or Blob is being read, and no error has occurred yet.
The read operation is complete. This could mean that: the entire File or Blob has been read into memory, a file read error occurred, or abort() was called and the read was cancelled.


var reader = new FileReader();
console.log('EMPTY', reader.readyState); // readyState will be 0

console.log('LOADING', reader.readyState); // readyState will be 1

reader.onloadend = function () {
    console.log('DONE', reader.readyState); // readyState will be 2


A number which is one of the three possible state constants define for the FileReader API:


Specification Status Comment
File API
The definition of 'FileReader' in that specification.
Working Draft Initial definition

Browser compatibilityUpdate compatibility data on GitHub

Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 7 Yes 3.6 10 11 6
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support ? Yes Yes 32 11 6.1 ?

See also

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