Document.readyState

Summary

The Document.readyState property of a document describes the loading state of the document.

Values

The readyState of a document can be one of following:

loading
The document is still loading.
interactive
The document has finished loading and the document has been parsed but sub-resources such as images, stylesheets and frames are still loading.
complete
The document and all sub-resources have finished loading. The state indicates that the load event is about to fire.

When the value of this property changes a readystatechange event fires on the document object.

Syntax

var string = document.readyState;

Examples

Different states of readiness

switch (document.readyState) {
  case "loading":
    // The document is still loading.
    break;
  case "interactive":
    // The document has finished loading. We can now access the DOM elements.
    var span = document.createElement("span");
    span.textContent = "A <span> element.";
    document.body.appendChild(span);
    break;
  case "complete":
    // The page is fully loaded.
    console.log("The first CSS rule is: " + document.styleSheets[0].cssRules[0].cssText);
    break;
}

readystatechange as an alternative to DOMContentLoaded event

// alternative to DOMContentLoaded event
document.onreadystatechange = function () {
  if (document.readyState === "interactive") {
    initApplication();
  }
}

readystatechange as an alternative to load event

// alternative to load event
document.onreadystatechange = function () {
  if (document.readyState === "complete") {
    initApplication();
  }
}

readystatechange as event listener to insert or modify the DOM before DOMContentLoaded

// early manipulation of the document <body> using an external script
var bootstrap = function(evt){
  if (evt.target.readyState === "interactive") { initLoader(); }
  else if (evt.target.readyState === "complete") { initApp(); }
} 
document.addEventListener('readystatechange', bootstrap, false);

Specification

Specification Status Comment
WHATWG HTML Living Standard
The definition of 'Document readiness' in that specification.		 Living Standard  
HTML 5.1
The definition of 'Document readiness' in that specification.		 Recommendation  
HTML5
The definition of 'Document readiness' in that specification.		 Recommendation Initial specification.

Browser compatibility

  
Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 5.0 (Yes) 4.0 4.0[3]8.0[1] 9.0[2] 11.0[1] 5.0
  
Feature Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 2.2 (Yes) 4.0 9[2] 11.0[1] 5.0

[1] Only support 'complete'. Opera Presto fire 'complete' late after the 'load' event (in an incorrect order as per HTML5 standard specification).

[2] Internet Explorer 9 and 10 have bugs where the 'interactive' state can be fired too early before the document has finished parsing.

[3] When introduced with IE 4, the property was available for only the document, embed, img, link, object, script, and style objects. IE 5 expanded coverage to all HTML element objects.

See also

Document Tags and Contributors

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 Contributors to this page: anonyco, hexalys, PageYe, erikadoyle, sijobling, teoli, sjakthol, sharq, kscarfone, gurdev_singh, Sheppy, ethertank, andyhume, louisremi, Yansky0, vali29, Crash
 Last updated by: anonyco,