---
title: XMLHttpRequestEventTarget.onload
slug: Web/API/XMLHttpRequestEventTarget/onload
translation_of: Web/API/XMLHttpRequestEventTarget/onload
---
{{APIRef("XMLHttpRequest")}}

The **`XMLHttpRequestEventTarget.onload`** is the function called when an {{domxref("XMLHttpRequest")}} transaction completes successfully.

## Syntax

    XMLHttpRequest.onload = callback;

### Values

- `callback` is the function to be executed when the request completes successfully. It receives a {{domxref("ProgressEvent")}} object as its first argument. The value of *this* (i.e. the context) is the same {{domxref("XMLHttpRequest")}} this callback is related to.

## Example

```js
var xmlhttp = new XMLHttpRequest(),
  method = 'GET',
  url = 'https://developer.mozilla.org/';

xmlhttp.open(method, url, true);
xmlhttp.onload = function () {
  // Do something with the retrieved data ( found in xmlhttp.response )
};
xmlhttp.send();
```

## Specifications

| Specification                                                            | Status                               | Comment                |
| ------------------------------------------------------------------------ | ------------------------------------ | ---------------------- |
| {{SpecName('XMLHttpRequest', '#handler-xhr-onload')}} | {{Spec2('XMLHttpRequest')}} | WHATWG living standard |

## Browser compatibility

{{Compat("api.XMLHttpRequestEventTarget.onload")}}