Do you have a list of all languages that are commonly used in html forms?
For html you can use this static code
<select data-placeholder="Choose a Language...">
<option value="AF">Afrikaans</option>
<option value="SQ">Albanian</option>
<option value="AR">Arabic</option>
<option value="HY">Armenian</option>
<option value="EU">Basque</option>
<option value="BN">Bengali</option>
<option value="BG">Bulgarian</option>
<option value="CA">Catalan</option>
<option value="KM">Cambodian</option>
<option value="ZH">Chinese (Mandarin)</option>
<option value="HR">Croatian</option>
<option value="CS">Czech</option>
<option value="DA">Danish</option>
<option value="NL">Dutch</option>
<option value="EN">English</option>
<option value="ET">Estonian</option>
<option value="FJ">Fiji</option>
<option value="FI">Finnish</option>
<option value="FR">French</option>
<option value="KA">Georgian</option>
<option value="DE">German</option>
<option value="EL">Greek</option>
<option value="GU">Gujarati</option>
<option value="HE">Hebrew</option>
<option value="HI">Hindi</option>
<option value="HU">Hungarian</option>
<option value="IS">Icelandic</option>
<option value="ID">Indonesian</option>
<option value="GA">Irish</option>
<option value="IT">Italian</option>
<option value="JA">Japanese</option>
<option value="JW">Javanese</option>
<option value="KO">Korean</option>
<option value="LA">Latin</option>
<option value="LV">Latvian</option>
<option value="LT">Lithuanian</option>
<option value="MK">Macedonian</option>
<option value="MS">Malay</option>
<option value="ML">Malayalam</option>
<option value="MT">Maltese</option>
<option value="MI">Maori</option>
<option value="MR">Marathi</option>
<option value="MN">Mongolian</option>
<option value="NE">Nepali</option>
<option value="NO">Norwegian</option>
<option value="FA">Persian</option>
<option value="PL">Polish</option>
<option value="PT">Portuguese</option>
<option value="PA">Punjabi</option>
<option value="QU">Quechua</option>
<option value="RO">Romanian</option>
<option value="RU">Russian</option>
<option value="SM">Samoan</option>
<option value="SR">Serbian</option>
<option value="SK">Slovak</option>
<option value="SL">Slovenian</option>
<option value="ES">Spanish</option>
<option value="SW">Swahili</option>
<option value="SV">Swedish </option>
<option value="TA">Tamil</option>
<option value="TT">Tatar</option>
<option value="TE">Telugu</option>
<option value="TH">Thai</option>
<option value="BO">Tibetan</option>
<option value="TO">Tonga</option>
<option value="TR">Turkish</option>
<option value="UK">Ukrainian</option>
<option value="UR">Urdu</option>
<option value="UZ">Uzbek</option>
<option value="VI">Vietnamese</option>
<option value="CY">Welsh</option>
<option value="XH">Xhosa</option>
</select>
Alternative method -:- without language code in value
<select data-placeholder="Choose a Language...">
<option value="Afrikaans">Afrikaans</option>
<option value="Albanian">Albanian</option>
<option value="Arabic">Arabic</option>
<option value="Armenian">Armenian</option>
<option value="Basque">Basque</option>
<option value="Bengali">Bengali</option>
<option value="Bulgarian">Bulgarian</option>
<option value="Catalan">Catalan</option>
<option value="Cambodian">Cambodian</option>
<option value="Chinese (Mandarin)">Chinese (Mandarin)</option>
<option value="Croatian">Croatian</option>
<option value="Czech">Czech</option>
<option value="Danish">Danish</option>
<option value="Dutch">Dutch</option>
<option value="English">English</option>
<option value="Estonian">Estonian</option>
<option value="Fiji">Fiji</option>
<option value="Finnish">Finnish</option>
<option value="French">French</option>
<option value="Georgian">Georgian</option>
<option value="German">German</option>
<option value="Greek">Greek</option>
<option value="Gujarati">Gujarati</option>
<option value="Hebrew">Hebrew</option>
<option value="Hindi">Hindi</option>
<option value="Hungarian">Hungarian</option>
<option value="Icelandic">Icelandic</option>
<option value="Indonesian">Indonesian</option>
<option value="Irish">Irish</option>
<option value="Italian">Italian</option>
<option value="Japanese">Japanese</option>
<option value="Javanese">Javanese</option>
<option value="Korean">Korean</option>
<option value="Latin">Latin</option>
<option value="Latvian">Latvian</option>
<option value="Lithuanian">Lithuanian</option>
<option value="Macedonian">Macedonian</option>
<option value="Malay">Malay</option>
<option value="Malayalam">Malayalam</option>
<option value="Maltese">Maltese</option>
<option value="Maori">Maori</option>
<option value="Marathi">Marathi</option>
<option value="Mongolian">Mongolian</option>
<option value="Nepali">Nepali</option>
<option value="Norwegian">Norwegian</option>
<option value="Persian">Persian</option>
<option value="Polish">Polish</option>
<option value="Portuguese">Portuguese</option>
<option value="Punjabi">Punjabi</option>
<option value="Quechua">Quechua</option>
<option value="Romanian">Romanian</option>
<option value="Russian">Russian</option>
<option value="Samoan">Samoan</option>
<option value="Serbian">Serbian</option>
<option value="Slovak">Slovak</option>
<option value="Slovenian">Slovenian</option>
<option value="Spanish">Spanish</option>
<option value="Swahili">Swahili</option>
<option value="Swedish ">Swedish </option>
<option value="Tamil">Tamil</option>
<option value="Tatar">Tatar</option>
<option value="Telugu">Telugu</option>
<option value="Thai">Thai</option>
<option value="Tibetan">Tibetan</option>
<option value="Tonga">Tonga</option>
<option value="Turkish">Turkish</option>
<option value="Ukrainian">Ukrainian</option>
<option value="Urdu">Urdu</option>
<option value="Uzbek">Uzbek</option>
<option value="Vietnamese">Vietnamese</option>
<option value="Welsh">Welsh</option>
<option value="Xhosa">Xhosa</option>
</select>
Demo
<select data-placeholder="Choose a Language...">
<option value="AF">Afrikaans</option>
<option value="SQ">Albanian</option>
<option value="AR">Arabic</option>
<option value="HY">Armenian</option>
<option value="EU">Basque</option>
<option value="BN">Bengali</option>
<option value="BG">Bulgarian</option>
<option value="CA">Catalan</option>
<option value="KM">Cambodian</option>
<option value="ZH">Chinese (Mandarin)</option>
<option value="HR">Croatian</option>
<option value="CS">Czech</option>
<option value="DA">Danish</option>
<option value="NL">Dutch</option>
<option value="EN">English</option>
<option value="ET">Estonian</option>
<option value="FJ">Fiji</option>
<option value="FI">Finnish</option>
<option value="FR">French</option>
<option value="KA">Georgian</option>
<option value="DE">German</option>
<option value="EL">Greek</option>
<option value="GU">Gujarati</option>
<option value="HE">Hebrew</option>
<option value="HI">Hindi</option>
<option value="HU">Hungarian</option>
<option value="IS">Icelandic</option>
<option value="ID">Indonesian</option>
<option value="GA">Irish</option>
<option value="IT">Italian</option>
<option value="JA">Japanese</option>
<option value="JW">Javanese</option>
<option value="KO">Korean</option>
<option value="LA">Latin</option>
<option value="LV">Latvian</option>
<option value="LT">Lithuanian</option>
<option value="MK">Macedonian</option>
<option value="MS">Malay</option>
<option value="ML">Malayalam</option>
<option value="MT">Maltese</option>
<option value="MI">Maori</option>
<option value="MR">Marathi</option>
<option value="MN">Mongolian</option>
<option value="NE">Nepali</option>
<option value="NO">Norwegian</option>
<option value="FA">Persian</option>
<option value="PL">Polish</option>
<option value="PT">Portuguese</option>
<option value="PA">Punjabi</option>
<option value="QU">Quechua</option>
<option value="RO">Romanian</option>
<option value="RU">Russian</option>
<option value="SM">Samoan</option>
<option value="SR">Serbian</option>
<option value="SK">Slovak</option>
<option value="SL">Slovenian</option>
<option value="ES">Spanish</option>
<option value="SW">Swahili</option>
<option value="SV">Swedish </option>
<option value="TA">Tamil</option>
<option value="TT">Tatar</option>
<option value="TE">Telugu</option>
<option value="TH">Thai</option>
<option value="BO">Tibetan</option>
<option value="TO">Tonga</option>
<option value="TR">Turkish</option>
<option value="UK">Ukrainian</option>
<option value="UR">Urdu</option>
<option value="UZ">Uzbek</option>
<option value="VI">Vietnamese</option>
<option value="CY">Welsh</option>
<option value="XH">Xhosa</option>
</select>