# Document: readystatechange event



The **`readystatechange`** event is fired when the [readyState](https://developer.mozilla.org/en-US/docs/Web/API/Document/readyState) attribute of a document has changed.

This event is not cancelable and does not bubble.

## Syntax

Use the event name in [addEventListener()](https://developer.mozilla.org/en-US/docs/Web/API/EventTarget%2FaddEventListener):

```js-nolint
addEventListener("readystatechange", (event) => { })
```

Alternatively, assign to the [event handler property](https://developer.mozilla.org/en-US/docs/Web/API/Document_Object_Model/Events#using_onevent_properties) of the interface:

```js-nolint
onreadystatechange = (event) => { }
```

## Event type

A generic [Event](https://developer.mozilla.org/en-US/docs/Web/API/Event).

## Examples

### Live example

#### HTML

```html
<div class="controls">
  <button id="reload" type="button">Reload</button>
</div>

<div class="event-log">
  <label for="eventLog">Event log:</label>
  <textarea
    readonly
    class="event-log-contents"
    rows="8"
    cols="30"
    id="eventLog"></textarea>
</div>
```

#### CSS

```css hidden
body {
  display: grid;
  grid-template-areas: "control log";
}

.controls {
  grid-area: control;
  display: flex;
  align-items: center;
  justify-content: center;
}

.event-log {
  grid-area: log;
}

.event-log-contents {
  resize: none;
}

label,
button {
  display: block;
}

#reload {
  height: 2rem;
}
```

#### JavaScript

```js
const log = document.querySelector(".event-log-contents");
const reload = document.querySelector("#reload");

reload.addEventListener("click", () => {
  log.textContent = "";
  setTimeout(() => {
    window.location.reload(true);
  }, 200);
});

window.addEventListener("load", (event) => {
  log.textContent = `${log.textContent}load\n`;
});

document.addEventListener("readystatechange", (event) => {
  log.textContent = `${log.textContent}readystate: ${document.readyState}\n`;
});

document.addEventListener("DOMContentLoaded", (event) => {
  log.textContent = `${log.textContent}DOMContentLoaded\n`;
});
```

#### Result

## Specifications

## Browser compatibility

## See also

- Related events: [`DOMContentLoaded`](https://developer.mozilla.org/en-US/docs/Web/API/Document/DOMContentLoaded_event), [`load`](https://developer.mozilla.org/en-US/docs/Web/API/Window/load_event), [`beforeunload`](https://developer.mozilla.org/en-US/docs/Web/API/Window/beforeunload_event), [`unload`](https://developer.mozilla.org/en-US/docs/Web/API/Window/unload_event)