TextDecoder()

This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The TextDecoder() constructor returns a newly created TextDecoder object for the encoding specified in parameter.

If the value for utfLabel is unknown, or is one of the two values leading to a 'replacement' decoding algorithm ( "iso-2022-cn" or "iso-2022-cn-ext"), a DOMException with the "TypeError" value is thrown.

Syntax

decoder = new TextDecoder(utfLabel, options); 

Parameters

utfLabel Optional
Is a DOMString, defaulting to "utf-8", containing the label of the encoder. Each label is associated with a specific encoding type:
Possible values of utfLabel Encoding
"unicode-1-1-utf-8", "utf-8", "utf8" 'utf-8'
"866", "cp866", "csibm866", "ibm866" 'ibm866'
"csisolatin2", "iso-8859-2", "iso-ir-101", "iso8859-2", "iso88592", "iso_8859-2", "iso_8859-2:1987", "l2", "latin2" 'iso-8859-2'
"csisolatin3", "iso-8859-3", "iso-ir-109", "iso8859-3", "iso88593", "iso_8859-3", "iso_8859-3:1988", "l3", "latin3" 'iso-8859-3'
"csisolatin4", "iso-8859-4", "iso-ir-110", "iso8859-4", "iso88594", "iso_8859-4", "iso_8859-4:1988", "l4", "latin4" 'iso-8859-4'
"csisolatincyrillic", "cyrillic", "iso-8859-5", "iso-ir-144", "iso88595", "iso_8859-5", "iso_8859-5:1988" 'iso-8859-5'
"arabic", "asmo-708", "csiso88596e", "csiso88596i", "csisolatinarabic", "ecma-114", "iso-8859-6", "iso-8859-6-e", "iso-8859-6-i", "iso-ir-127", "iso8859-6", "iso88596", "iso_8859-6", "iso_8859-6:1987" 'iso-8859-6'
"csisolatingreek", "ecma-118", "elot_928", "greek", "greek8", "iso-8859-7", "iso-ir-126", "iso8859-7", "iso88597", "iso_8859-7", "iso_8859-7:1987", "sun_eu_greek" 'iso-8859-7'
"csiso88598e", "csisolatinhebrew", "hebrew", "iso-8859-8", "iso-8859-8-e", "iso-ir-138", "iso8859-8", "iso88598", "iso_8859-8", "iso_8859-8:1988", "visual" 'iso-8859-8'
"csiso88598i", "iso-8859-8-i", "logical" 'iso-8859-8i'
"csisolatin6", "iso-8859-10", "iso-ir-157", "iso8859-10", "iso885910", "l6", "latin6" 'iso-8859-10'
"iso-8859-13", "iso8859-13", "iso885913" 'iso-8859-13'
"iso-8859-14", "iso8859-14", "iso885914" 'iso-8859-14'
"csisolatin9", "iso-8859-15", "iso8859-15", "iso885915", "l9", "latin9" 'iso-8859-15'
"iso-8859-16" 'iso-8859-16'
"cskoi8r", "koi", "koi8", "koi8-r", "koi8_r" 'koi8-r'
"koi8-u" 'koi8-u'
"csmacintosh", "mac", "macintosh", "x-mac-roman" 'macintosh'
"dos-874", "iso-8859-11", "iso8859-11", "iso885911", "tis-620", "windows-874" 'windows-874'
"cp1250", "windows-1250", "x-cp1250" 'windows-1250'
"cp1251", "windows-1251", "x-cp1251" 'windows-1251'
"ansi_x3.4-1968", "ascii", "cp1252", "cp819", "csisolatin1", "ibm819", "iso-8859-1", "iso-ir-100", "iso8859-1", "iso88591", "iso_8859-1", "iso_8859-1:1987", "l1", "latin1", "us-ascii", "windows-1252", "x-cp1252" 'windows-1252'
"cp1253", "windows-1253", "x-cp1253" 'windows-1253'
"cp1254", "csisolatin5", "iso-8859-9", "iso-ir-148", "iso8859-9", "iso88599", "iso_8859-9", "iso_8859-9:1989", "l5", "latin5", "windows-1254", "x-cp1254" 'windows-1254'
"cp1255", "windows-1255", "x-cp1255" 'windows-1255'
"cp1256", "windows-1256", "x-cp1256" 'windows-1256'
"cp1257", "windows-1257", "x-cp1257" 'windows-1257'
"cp1258", "windows-1258", "x-cp1258" 'windows-1258'
"x-mac-cyrillic", "x-mac-ukrainian" 'x-mac-cyrillic'
"chinese", "csgb2312", "csiso58gb231280", "gb2312", "gb_2312", "gb_2312-80", "gbk", "iso-ir-58", "x-gbk" 'gbk'
"gb18030" 'gb18030'
"hz-gb-2312" 'hz-gb-2312'
"big5", "big5-hkscs", "cn-big5", "csbig5", "x-x-big5" 'big5'
"cseucpkdfmtjapanese", "euc-jp", "x-euc-jp" 'euc-jp'

"csiso2022jp", "iso-2022-jp"

Note: Firefox used to accept iso-2022-jp-2 sequences silently when an iso-2022-jp decoder was instantiated, however this was removed in version 56 to simplify the API, as no other browsers support it and no pages seem to use it.

'iso-2022-jp'
"csshiftjis", "ms_kanji", "shift-jis", "shift_jis", "sjis", "windows-31j", "x-sjis" 'shift-jis'
"cseuckr", "csksc56011987", "euc-kr", "iso-ir-149", "korean", "ks_c_5601-1987", "ks_c_5601-1989", "ksc5601", "ksc_5601", "windows-949" 'euc-kr'
"csiso2022kr", "iso-2022-kr" 'iso-2022-kr'
"utf-16be" 'utf-16be'
"utf-16", "utf-16le" 'utf-16le'
"x-user-defined" 'x-user-defined'
"iso-2022-cn", "iso-2022-cn-ext" 'replacement'
options Optional
Is a TextDecoderOptions dictionary with the property:
fatal
A Boolean flag indicating if the TextDecoder.decode() method must throw a DOMException with the "EncodingError" value when an coding error is found. It defaults to false.

Example

var textDecoder1 = new TextDecoder("iso-8859-2");
var textDecoder2 = new TextDecoder();
var textDecoder3 = new TextDecoder("csiso2022kr", {fatal: true}); // Allows EncodingError exception to be thrown.
var textDecoder4 = new TextDecoder("iso-2022-cn"); // Throw a TypeError exception.

Specifications

Specification Status Comment
Encoding
The definition of 'TextDecoder()' in that specification.
Living Standard Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 38 19.0 (19.0) [1] No support 25 ?
Available in Web Workers 38 20.0 (20.0) No support 25 ?
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support No support 38.0 19.0 (19.0) [1] 1.0.1 (19.0) No support ? No support 38.0
Available in Web Workers No support 38.0 20.0 (20.0) 1.0.1 (20.0) No support ? No support 38.0

[1] An earlier, and slightly different, version of the specification was implemented in Firefox 18.

See also

Document Tags and Contributors

 Contributors to this page: chrisdavidmills, jpmedley, fscholz, jscissr, Rob W, Reachmeatshivam, teoli
 Last updated by: chrisdavidmills,