Web/API/XMLHTTPRequest/send

The XMLHttpRequest method send() sends the request to the server. If the request is asynchronous (which is the default), this method returns as soon as the request is sent and the result is delivered using events. If the request is synchronous, this method doesn't return until the response has arrived.

send() accepts an optional parameter which lets you specify the request's body; this is primarily used for requests such as PUT. If the request method is GET or HEAD, the body parameter is ignored and the request body is set to null.

If no Accept header has been set using the setRequestHeader(), an Accept header with the type "*/*" (any type) is sent.

Syntax

XMLHttpRequest.send(body)

Parameters

body Optional

A body of data to be sent in the XHR request. This can be:

A Document, in which case it is serialized before being sent.
An XMLHttpRequestBodyInit, which per the Fetch spec can be a Blob, BufferSource, FormData, URLSearchParams, or USVString object.
null

If no value is specified for the body, a default value of null is used.

The best way to send binary content (e.g. in file uploads) is by using an ArrayBufferView or Blob in conjunction with the send() method.

Return value

undefined.

Exceptions

Exception	Description
`InvalidStateError`	`send()` has already been invoked for the request, and/or the request is complete.
`NetworkError`	The resource type to be fetched is a Blob, and the method is not `GET`.

Example: GET

var xhr = new XMLHttpRequest();
xhr.open('GET', '/server', true);

xhr.onload = function () {
  // Request finished. Do processing here.
};

xhr.send(null);
// xhr.send('string');
// xhr.send(new Blob());
// xhr.send(new Int8Array());
// xhr.send(document);

Example: POST

var xhr = new XMLHttpRequest();
xhr.open("POST", '/server', true);

//Send the proper header information along with the request
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");

xhr.onreadystatechange = function() { // Call a function when the state changes.
    if (this.readyState === XMLHttpRequest.DONE && this.status === 200) {
        // Request finished. Do processing here.
    }
}
xhr.send("foo=bar&lorem=ipsum");
// xhr.send(new Int8Array()); 
// xhr.send(document);

Specifications

Specification	Status	Comment
XMLHttpRequestThe definition of 'send()' in that specification.	Living Standard	WHATWG living standard

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`send`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 5	Opera Full support 8	Safari Full support 1.2	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0
ArrayBuffer as parameter to send()	Chrome Full support 9	Edge Full support 12	Firefox Full support 9	IE Full support 10	Opera Full support 11.6	Safari Full support Yes	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 9	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support Yes
ArrayBufferView as parameter to send()	Chrome Full support 22	Edge Full support ≤79	Firefox Full support 20	IE ?	Opera Full support Yes	Safari ?	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 20	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support Yes
Blob as parameter to send()	Chrome Full support 22	Edge Full support 12	Firefox Full support 2	IE Full support 10	Opera Full support 12	Safari ?	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 4	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support Yes
FormData as parameter to send()	Chrome Full support 6	Edge Full support 12	Firefox Full support 2	IE Full support 10	Opera Full support 12	Safari ?	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 4	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support Yes
URLSearchParams as parameter to send()	Chrome Full support 59	Edge Full support ≤79	Firefox Full support 44	IE ?	Opera Full support 12	Safari ?	WebView Android Full support Yes	Chrome Android Full support 59	Firefox Android Full support 44	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support 7.0

Legend

Full support: Full support
Compatibility unknown: Compatibility unknown