The FormData interface provides a way to easily construct a set of key/value pairs representing form fields and their values, which can then be easily sent using the XMLHttpRequest.send() method. It uses the same format a form would use if the encoding type were set to "multipart/form-data".

An object implementing FormData can directly be used in a for...of structure, instead of entries(): for (var p of myFormData) is equivalent to for (var p of myFormData.entries()).

Note: This feature is available in Web Workers.

Constructor

FormData()
Creates a new FormData object.

Methods

FormData.append()
Appends a new value onto an existing key inside a FormData object, or adds the key if it does not already exist.
FormData.delete()
Deletes a key/value pair from a FormData object.
FormData.entries()
Returns an iterator allowing to go through all key/value pairs contained in this object.
FormData.get()
Returns the first value associated with a given key from within a FormData object.
FormData.getAll()
Returns an array of all the values associated with a given key from within a FormData.
FormData.has()
Returns a boolean stating whether a FormData object contains a certain key.
FormData.keys()
Returns an iterator allowing to go through all keys of the key/value pairs contained in this object.
FormData.set()
Sets a new value for an existing key inside a FormData object, or adds the key/value if it does not already exist.
FormData.values()
Returns an iterator allowing to go through all values  contained in this object.

Specifications

Specification Status Comment
XMLHttpRequest
The definition of 'FormData' in that specification.
Living Standard FormData defined in XHR spec

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support 7Edge Full support YesFirefox Full support 4
Notes
Full support 4
Notes
Notes Prior to Firefox 7, specifying a Blob as the data to append to the object, the filename reported in the Content-Disposition HTTP header was an empty string, resulting in errors on some servers. Starting with Firefox 7, the filename blob is sent.
IE Full support 10Opera Full support 12Safari Full support 5WebView Android Full support Yes
Notes
Full support Yes
Notes
Notes XHR in Android 4.0 sends empty content for FormData with blob.
Chrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 4Opera Android Full support 12Safari iOS ? Samsung Internet Android ?
FormData() constructorChrome Full support 7Edge Full support YesFirefox Full support 4IE Full support 10Opera Full support 12Safari Full support 5WebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support YesOpera Android Full support 12Safari iOS ? Samsung Internet Android ?
appendChrome Full support 7Edge Full support YesFirefox Full support 4
Notes
Full support 4
Notes
Notes Prior to Firefox 7, specifying a Blob as the data to append to the object, the filename reported in the Content-Disposition HTTP header was an empty string, resulting in errors on some servers. Starting with Firefox 7, the filename blob is sent.
IE Full support 10
Notes
Full support 10
Notes
Notes With the "Include local directory pass when uploading files to a server" option enabled, IE will change the filename inside the Blob on the fly. To have direct control of the sent filename, the developer should send the filename as the third parameter value, i.e. formData.append(name, value, filename).
Opera Full support 12Safari Full support 5WebView Android Full support 3
Notes
Full support 3
Notes
Notes XHR in Android 4.0 sends empty content for FormData with blob.
Chrome Android ? Edge Mobile Full support YesFirefox Android Full support 4
Notes
Full support 4
Notes
Notes Prior to Firefox 7, specifying a Blob as the data to append to the object, the filename reported in the Content-Disposition HTTP header was an empty string, resulting in errors on some servers. Starting with Firefox 7, the filename blob is sent.
Opera Android Full support 12Safari iOS ? Samsung Internet Android ?
deleteChrome Full support 50Edge No support NoFirefox Full support 39IE No support NoOpera Full support YesSafari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support YesOpera Android Full support YesSafari iOS No support NoSamsung Internet Android ?
getChrome Full support 50Edge No support NoFirefox Full support 39IE No support NoOpera Full support YesSafari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support YesOpera Android Full support YesSafari iOS No support NoSamsung Internet Android ?
getAllChrome Full support 50Edge No support NoFirefox Full support 39IE No support NoOpera Full support YesSafari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support YesOpera Android Full support YesSafari iOS No support NoSamsung Internet Android ?
hasChrome Full support 50Edge No support NoFirefox Full support 39IE No support NoOpera Full support YesSafari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support YesOpera Android Full support YesSafari iOS No support NoSamsung Internet Android ?
setChrome Full support 50Edge No support NoFirefox Full support 39IE No support NoOpera No support NoSafari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support YesOpera Android No support NoSafari iOS No support NoSamsung Internet Android ?
entriesChrome Full support 50Edge No support NoFirefox Full support 44IE No support NoOpera Full support YesSafari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support 44Opera Android Full support YesSafari iOS ? Samsung Internet Android ?
keysChrome Full support 50Edge No support NoFirefox Full support 44IE ? Opera Full support YesSafari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support 44Opera Android ? Safari iOS ? Samsung Internet Android ?
valuesChrome Full support 50Edge No support NoFirefox Full support 44IE ? Opera ? Safari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support 44Opera Android ? Safari iOS ? Samsung Internet Android ?
Support of for...ofChrome Full support 50Edge No support NoFirefox Full support 44IE ? Opera ? Safari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support 44Opera Android ? Safari iOS ? Samsung Internet Android ?
Available in workersChrome Full support YesEdge Full support YesFirefox Full support 39IE No support NoOpera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support YesOpera Android Full support YesSafari iOS No support NoSamsung Internet Android ?

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
See implementation notes.
See implementation notes.

See also