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.


decoder = new TextDecoder(utfLabel, options); 


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.

"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:
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.


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.


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

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support38 ?



FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support3838 ?



? No ?

1. Implemented a slightly different version of the spec.

See also

Document Tags and Contributors

Last updated by: fscholz,