What are language codes in Chrome's implementation of the HTML5 speech recognition API?

Ok, if it is not published, we can try to at least figure this out.Let me put this table for the beginning and we will refine it if someone has more information.

I'm making assumption that supported languages shall be similar to those supported by voice search and that google uses standard language codes and does that consistently across its services.

I've looked up languages supported by voice search on wikipedia

I've found language codes here, on google language settings page and here

EDIT:I've experimented with backend voice recognition service. I've run a series of tests where I've passed the same english speech sample to the API but specified different dialect every time. It looks like:

• If a language is not supported, recognition falls back to en-US (looks like it recognizes that the sample is in english)
• If a dialect is not supported (or doesn't exist) recognition falls back to main dialect or en-US in some cases
• Main dialect can be specified just as first part of identifier. So 'en-US' and 'en' gives same results.
• Recognition for some languages, like chinese and japanese gives results in english, different from en-US though, which is strange. Probably the sample is different very much from chinese and the service is clever to figure that out.

I treat a dialect as supported if recognition gives a different result from en-US and from main dialect for the language. Still, to verify it 100% we need to run samples for each language.

Legend

• + Most of all supported, because test gives a result different from en-US and main dialect.
• .+ Absent on wikipedia but most of all supported, because test gives result different from en-US and main dialect.
• +? Most of all supported because it is listed on wikipedia. But test on my sample gives result identical to the main dialect. So either this is a coinsidense or language code is wrong.
• .+? Not listed on wikipedia but looks like supported, because test gives result different from en-US and main dialect.

Languages

• + Afrikaans af
• + Basque eu
• + Bulgarian bg
• + Catalan ca
• + Arabic (Egypt) ar-EG
• +? Arabic (Jordan) ar-JO
• + Arabic (Kuwait) ar-KW
• +? Arabic (Lebanon) ar-LB
• + Arabic (Qatar) ar-QA
• + Arabic (UAE) ar-AE
• .+ Arabic (Morocco) ar-MA
• .+ Arabic (Iraq) ar-IQ
• .+ Arabic (Algeria) ar-DZ
• .+ Arabic (Bahrain) ar-BH
• .+ Arabic (Lybia) ar-LY
• .+ Arabic (Oman) ar-OM
• .+ Arabic (Saudi Arabia) ar-SA
• .+ Arabic (Tunisia) ar-TN
• .+ Arabic (Yemen) ar-YE
• + Czech cs
• + Dutch nl-NL
• + English (Australia) en-AU
• +? English (Canada) en-CA
• + English (India) en-IN
• + English (New Zealand) en-NZ
• + English (South Africa) en-ZA
• + English(UK) en-GB
• + English(US) en-US
• + Finnish fi
• + French fr-FR
• + Galician gl
• + German de-DE
• + Hebrew he
• + Hungarian hu
• + Icelandic is
• + Italian it-IT
• + Indonesian id
• + Japanese ja
• + Korean ko
• + Latin la
• + Mandarin Chinese zh-CN
• + Traditional Taiwan zh-TW
• +? Simplified China zh-CN ?
• + Simplified Hong Kong zh-HK
• + Yue Chinese (Traditional Hong Kong) zh-yue
• + Malaysian ms-MY
• + Norwegian no-NO
• + Polish pl
• +? Pig Latin xx-piglatin
• + Portuguese pt-PT
• .+ Portuguese (brasil) pt-BR
• + Romanian ro-RO
• + Russian ru
• + Serbian sr-SP
• + Slovak sk
• + Spanish (Argentina) es-AR
• + Spanish(Bolivia) es-BO
• +? Spanish( Chile) es-CL
• +? Spanish (Colombia) es-CO
• +? Spanish(Costa Rica) es-CR
• + Spanish(Dominican Republic) es-DO
• + Spanish(Ecuador) es-EC
• + Spanish(El Salvador) es-SV
• + Spanish(Guatemala) es-GT
• + Spanish(Honduras) es-HN
• + Spanish(Mexico) es-MX
• + Spanish(Nicaragua) es-NI
• + Spanish(Panama) es-PA
• + Spanish(Paraguay) es-PY
• + Spanish(Peru) es-PE
• + Spanish(Puerto Rico) es-PR
• + Spanish(Spain) es-ES
• + Spanish(US) es-US
• + Spanish(Uruguay) es-UY
• + Spanish(Venezuela) es-VE
• + Swedish sv-SE
• + Turkish tr
• + Zulu zu

I know this is an old post, but since this information is annoyingly hard to find I thought I'd post a list for anyone who might be looking. Please leave a note if you find any errors or omissions.

{  "Afrikaans": [    ["South Africa", "af-ZA"]  ],  "Arabic" : [    ["Algeria","ar-DZ"],    ["Bahrain","ar-BH"],    ["Egypt","ar-EG"],    ["Israel","ar-IL"],    ["Iraq","ar-IQ"],    ["Jordan","ar-JO"],    ["Kuwait","ar-KW"],    ["Lebanon","ar-LB"],    ["Morocco","ar-MA"],    ["Oman","ar-OM"],    ["Palestinian Territory","ar-PS"],    ["Qatar","ar-QA"],    ["Saudi Arabia","ar-SA"],    ["Tunisia","ar-TN"],    ["UAE","ar-AE"]  ],  "Basque": [    ["Spain", "eu-ES"]  ],  "Bulgarian": [    ["Bulgaria", "bg-BG"]  ],  "Catalan": [    ["Spain", "ca-ES"]  ],  "Chinese Mandarin": [    ["China (Simp.)", "cmn-Hans-CN"],    ["Hong Kong SAR (Trad.)", "cmn-Hans-HK"],    ["Taiwan (Trad.)", "cmn-Hant-TW"]  ],  "Chinese Cantonese": [    ["Hong Kong", "yue-Hant-HK"]  ],  "Croatian": [    ["Croatia", "hr_HR"]  ],  "Czech": [    ["Czech Republic", "cs-CZ"]  ],  "Danish": [    ["Denmark", "da-DK"]  ],  "English": [    ["Australia", "en-AU"],    ["Canada", "en-CA"],    ["India", "en-IN"],    ["Ireland", "en-IE"],    ["New Zealand", "en-NZ"],    ["Philippines", "en-PH"],    ["South Africa", "en-ZA"],    ["United Kingdom", "en-GB"],    ["United States", "en-US"]  ],  "Farsi": [    ["Iran", "fa-IR"]  ],  "French": [    ["France", "fr-FR"]  ],  "Filipino": [    ["Philippines", "fil-PH"]  ],  "Galician": [    ["Spain", "gl-ES"]  ],  "German": [    ["Germany", "de-DE"]  ],  "Greek": [    ["Greece", "el-GR"]  ],  "Finnish": [    ["Finland", "fi-FI"]  ],  "Hebrew" :[    ["Israel", "he-IL"]  ],  "Hindi": [    ["India", "hi-IN"]  ],  "Hungarian": [    ["Hungary", "hu-HU"]  ],  "Indonesian": [    ["Indonesia", "id-ID"]  ],  "Icelandic": [    ["Iceland", "is-IS"]  ],  "Italian": [    ["Italy", "it-IT"],    ["Switzerland", "it-CH"]  ],  "Japanese": [    ["Japan", "ja-JP"]  ],  "Korean": [    ["Korea", "ko-KR"]  ],  "Lithuanian": [    ["Lithuania", "lt-LT"]  ],  "Malaysian": [    ["Malaysia", "ms-MY"]  ],  "Dutch": [    ["Netherlands", "nl-NL"]  ],  "Norwegian": [    ["Norway", "nb-NO"]  ],  "Polish": [    ["Poland", "pl-PL"]  ],  "Portuguese": [    ["Brazil", "pt-BR"],    ["Portugal", "pt-PT"]  ],  "Romanian": [    ["Romania", "ro-RO"]  ],  "Russian": [    ["Russia", "ru-RU"]  ],  "Serbian": [    ["Serbia", "sr-RS"]  ],  "Slovak": [    ["Slovakia", "sk-SK"]  ],  "Slovenian": [    ["Slovenia", "sl-SI"]  ],  "Spanish": [    ["Argentina", "es-AR"],    ["Bolivia", "es-BO"],    ["Chile", "es-CL"],    ["Colombia", "es-CO"],    ["Costa Rica", "es-CR"],    ["Dominican Republic", "es-DO"],    ["Ecuador", "es-EC"],    ["El Salvador", "es-SV"],    ["Guatemala", "es-GT"],    ["Honduras", "es-HN"],    ["México", "es-MX"],    ["Nicaragua", "es-NI"],    ["Panamá", "es-PA"],    ["Paraguay", "es-PY"],    ["Perú", "es-PE"],    ["Puerto Rico", "es-PR"],    ["Spain", "es-ES"],    ["Uruguay", "es-UY"],    ["United States", "es-US"],    ["Venezuela", "es-VE"]  ],  "Swedish": [    ["Sweden", "sv-SE"]  ],  "Thai": [    ["Thailand", "th-TH"]  ],  "Turkish": [    ["Turkey", "tr-TR"]  ],  "Ukrainian": [    ["Ukraine", "uk-UA"]  ],  "Vietnamese": [    ["Viet Nam", "vi-VN"]  ],  "Zulu": [    ["South Africa", "zu-ZA"]  ]}

Edit: I also found this list, which is probably more current:https://cloud.google.com/speech-to-text/docs/languages

Use the following code to get all available voices for the speech API in your browser:

var voices = speechSynthesis.getVoices();      for(var i = 0; i < voices.length; i++ ) {        console.log("Voice " + i.toString() + ' ' + voices[i].name + ' ' + voices[i].uri);      }

At this time only Chrome and Safari support the Web Speech API (although Safari only supports the Text to Speech functionalities). Curiously Firefox OS supports TTS but the browser version does not.

The list of languages depends on what browser you are on according to both the documentation and my tests (user agent dependent).

In Safari you also get lots of languages available (I believe over 40). In Chrome, at this time you get the following list:

Voice 0 Google US English undefined

Voice 1 Google UK English Male undefined

Voice 2 Google UK English Female undefined

Voice 3 Google Español undefined

Voice 4 Google Français undefined

Voice 5 Google Italiano undefined

Voice 6 Google Deutsch undefined

Voice 7 Google 日本人 undefined

Voice 8 Google 한국의 undefined

Voice 9 Google 中国的 undefined

Voice 10 native undefined