How to Get the List of Available Locales in PHP

Is there a way to get the list of available locales in PHP?

Part of the confusion here is that PHP has two concepts called "locale" that are pretty much totally separate.

The first is the older one, which basically just uses the C locale features. That's what's behind setlocale and the locale support in some of PHP's functions (like money_format for example). This is what other answers that mention running locale -a on the command line and using setlocale are talking about.

PHP's Locale class and the other related functionality from the intl extension is newer, and doesn't work the same way. Instead of using the libc locale stuff, it uses a library called ICU, which ships its own locale data. PHP does provide a method to determine which locales are supported by this system: ResourceBundle::getLocales. The documentation is a little wooly here, but you can call this as a static method and pass the blank string to use ICU's default resources, thus getting a list of the supported locales for intl:

ResourceBundle::getLocales('');

List of All Locales and Their Short Codes?

The importance of locales is that your environment/os can provide formatting functionality for all installed locales even if you don't know about them when you write your application. My Windows 7 system has 211 locales installed (listed below), so you wouldn't likely write any custom code or translation specific to this many locales.

Edit: The original list of locales has been edited to add additional locales that were not included before. Now 228 listed.

The most important thing for various versions of English is in formatting numbers and dates. Other differences are significant to the extent that you want and able to cater to specific variations.

af-ZA
am-ET
ar-AE
ar-BH
ar-DZ
ar-EG
ar-IQ
ar-JO
ar-KW
ar-LB
ar-LY
ar-MA
arn-CL
ar-OM
ar-QA
ar-SA
ar-SD
ar-SY
ar-TN
ar-YE
as-IN
az-az
az-Cyrl-AZ
az-Latn-AZ
ba-RU
be-BY
bg-BG
bn-BD
bn-IN
bo-CN
br-FR
bs-Cyrl-BA
bs-Latn-BA
ca-ES
co-FR
cs-CZ
cy-GB
da-DK
de-AT
de-CH
de-DE
de-LI
de-LU
dsb-DE
dv-MV
el-CY
el-GR
en-029
en-AU
en-BZ
en-CA
en-cb
en-GB
en-IE
en-IN
en-JM
en-MT
en-MY
en-NZ
en-PH
en-SG
en-TT
en-US
en-ZA
en-ZW
es-AR
es-BO
es-CL
es-CO
es-CR
es-DO
es-EC
es-ES
es-GT
es-HN
es-MX
es-NI
es-PA
es-PE
es-PR
es-PY
es-SV
es-US
es-UY
es-VE
et-EE
eu-ES
fa-IR
fi-FI
fil-PH
fo-FO
fr-BE
fr-CA
fr-CH
fr-FR
fr-LU
fr-MC
fy-NL
ga-IE
gd-GB
gd-ie
gl-ES
gsw-FR
gu-IN
ha-Latn-NG
he-IL
hi-IN
hr-BA
hr-HR
hsb-DE
hu-HU
hy-AM
id-ID
ig-NG
ii-CN
in-ID
is-IS
it-CH
it-IT
iu-Cans-CA
iu-Latn-CA
iw-IL
ja-JP
ka-GE
kk-KZ
kl-GL
km-KH
kn-IN
kok-IN
ko-KR
ky-KG
lb-LU
lo-LA
lt-LT
lv-LV
mi-NZ
mk-MK
ml-IN
mn-MN
mn-Mong-CN
moh-CA
mr-IN
ms-BN
ms-MY
mt-MT
nb-NO
ne-NP
nl-BE
nl-NL
nn-NO
no-no
nso-ZA
oc-FR
or-IN
pa-IN
pl-PL
prs-AF
ps-AF
pt-BR
pt-PT
qut-GT
quz-BO
quz-EC
quz-PE
rm-CH
ro-mo
ro-RO
ru-mo
ru-RU
rw-RW
sah-RU
sa-IN
se-FI
se-NO
se-SE
si-LK
sk-SK
sl-SI
sma-NO
sma-SE
smj-NO
smj-SE
smn-FI
sms-FI
sq-AL
sr-BA
sr-CS
sr-Cyrl-BA
sr-Cyrl-CS
sr-Cyrl-ME
sr-Cyrl-RS
sr-Latn-BA
sr-Latn-CS
sr-Latn-ME
sr-Latn-RS
sr-ME
sr-RS
sr-sp
sv-FI
sv-SE
sw-KE
syr-SY
ta-IN
te-IN
tg-Cyrl-TJ
th-TH
tk-TM
tlh-QS
tn-ZA
tr-TR
tt-RU
tzm-Latn-DZ
ug-CN
uk-UA
ur-PK
uz-Cyrl-UZ
uz-Latn-UZ
uz-uz
vi-VN
wo-SN
xh-ZA
yo-NG
zh-CN
zh-HK
zh-MO
zh-SG
zh-TW
zu-ZA

PHP- Get current locale

You can call setlocale like so, and it'll return the current local.

$currentLocale = setlocale(LC_ALL, 0);
echo $currentLocale; //outputs C/en_US.UTF-8/C/C/C/C on my machine

Here is documentation from php.net as commented by @JROB

locale
If locale is "0", the locale setting is not affected, only the current setting is returned.
If locale is NULL or the empty string "", the locale names will be set from the values of environment variables with the same names as the above categories, or from "LANG".
If locale is an array or followed by additional parameters then each array element or parameter is tried to be set as new locale until success. This is useful if a locale is known under different names on different systems or for providing a fallback for a possibly not available locale.

List of available collators in PHP?

I think the Collator is using the locale information from the CLDR repository.

I compiled a list from it's current trunk (at the time of writing: 2020-02-23):

af          af_NA       af_ZA       ar          ar_001      ar_AE       
ar_BH       ar_DZ       ar_EG       ar_IQ       ar_JO       ar_KW       
ar_LB       ar_LY       ar_MA       ar_OM       ar_QA       ar_SA       
ar_SD       ar_SY       ar_TN       ar_YE       as          as_IN       
az          az_Latn     az_Latn_AZ  be          be_BY       bg          
bg_BG       bn          bn_BD       bn_IN       bs          bs_BA       
ca          ca_ES       chr         chr_US      cs          cs_CZ       
cy          cy_GB       da          da_DK       de          de_AT       
de_BE       de_CH       de_DE       de_LI       de_LU       dz          
ee          ee_GH       ee_TG       el          el_CY       el_GR       
en          en_AS       en_AU       en_BB       en_BE       en_BM       
en_BW       en_BZ       en_CA       en_GB       en_GU       en_HK       
en_IE       en_IN       en_JM       en_MH       en_MP       en_MT       
en_MU       en_NA       en_NZ       en_PH       en_PK       en_SG       
en_TT       en_UM       en_US       en_US_POSIX en_VI       en_ZA       
en_ZW       eo          es          es_419      es_AR       es_BO       
es_CL       es_CO       es_CR       es_DO       es_EC       es_ES       
es_GQ       es_GT       es_HN       es_MX       es_NI       es_PA       
es_PE       es_PR       es_PY       es_SV       es_US       es_UY       
es_VE       et          et_EE       fa          fa_AF       fa_IR       
fi          fi_FI       fil         fil_PH      fo          fo_FO       
fr          fr_BE       fr_BF       fr_BI       fr_BJ       fr_BL       
fr_CA       fr_CD       fr_CF       fr_CG       fr_CH       fr_CI       
fr_CM       fr_DJ       fr_FR       fr_GA       fr_GN       fr_GP       
fr_GQ       fr_KM       fr_LU       fr_MC       fr_MF       fr_MG       
fr_ML       fr_MQ       fr_NE       fr_RE       fr_RW       fr_SN       
fr_TD       fr_TG       ga          ga_IE       gu          gu_IN       
ha          ha_Latn     ha_Latn_GH  ha_Latn_NE  ha_Latn_NG  haw         
haw_US      he          he_IL       hi          hi_IN       hr          
hr_HR       hu          hu_HU       hy          hy_AM       id          
id_ID       ig          ig_NG       is          is_IS       it          
it_CH       it_IT       ja          ja_JP       ka          ka_GE       
kk          kk_KZ       kl          kl_GL       km          km_KH       
kn          kn_IN       ko          ko_KR       kok         kok_IN      
ky          ky_KG       ln          ln_CD       ln_CG       lt          
lt_LT       lv          lv_LV       mk          mk_MK       ml          
ml_IN       mr          mr_IN       ms          ms_BN       ms_MY       
mt          mt_MT       my          my_MM       nb          nb_NO       
nl          nl_AW       nl_BE       nl_CW       nl_NL       nl_SX       
nn          nn_NO       nso         nso_ZA      om          om_ET       
om_KE       or          or_IN       pa          pa_Arab     pa_Arab_PK  
pa_Guru     pa_Guru_IN  pl          pl_PL       ps          ps_AF       
pt          pt_AO       pt_BR       pt_GW       pt_MZ       pt_PT       
pt_ST       ro          ro_MD       ro_RO       ru          ru_MD       
ru_RU       ru_UA       se          se_FI       se_NO       si          
si_LK       sk          sk_SK       sl          sl_SI       sq          
sq_AL       sr          sr_Cyrl     sr_Cyrl_BA  sr_Cyrl_ME  sr_Cyrl_RS  
sr_Latn     sr_Latn_BA  sr_Latn_ME  sr_Latn_RS  st          st_LS       
st_ZA       sv          sv_FI       sv_SE       sw          sw_KE       
sw_TZ       ta          ta_IN       ta_LK       te          te_IN       
th          th_TH       tn          tn_ZA       to          to_TO       
tr          tr_TR       uk          uk_UA       ur          ur_IN       
ur_PK       vi          vi_VN       wae         wae_CH      xh          
xh_ZA       yo          yo_NG       zh          zh_Hans     zh_Hans_CN  
zh_Hans_SG  zh_Hant     zh_Hant_HK  zh_Hant_MO  zh_Hant_TW  zu          
zu_ZA

Or grouped:

af (af_NA, af_ZA)
ar (ar_001, ar_AE, ar_BH, ar_DZ, ar_EG, ar_IQ, ar_JO, ar_KW, ar_LB, ar_LY, ar_MA, ar_OM, ar_QA, ar_SA, ar_SD, ar_SY, ar_TN, ar_YE)
as (as_IN)
az (az_Latn, az_Latn_AZ)
be (be_BY)
bg (bg_BG)
bn (bn_BD, bn_IN)
bs (bs_BA)
ca (ca_ES)
cs (cs_CZ)
cy (cy_GB)
da (da_DK)
de (de_AT, de_BE, de_CH, de_DE, de_LI, de_LU)
dz
ee (ee_GH, ee_TG)
el (el_CY, el_GR)
en (en_AS, en_AU, en_BB, en_BE, en_BM, en_BW, en_BZ, en_CA, en_GB, en_GU, en_HK, en_IE, en_IN, en_JM, en_MH, en_MP, en_MT, en_MU, en_NA, en_NZ, en_PH, en_PK, en_SG, en_TT, en_UM, en_VI, en_ZA, en_ZW)
en_US
en_US_POSIX
eo
es (es_419, es_AR, es_BO, es_CL, es_CO, es_CR, es_DO, es_EC, es_ES, es_GQ, es_GT, es_HN, es_MX, es_NI, es_PA, es_PE, es_PR, es_PY, es_SV, es_US, es_UY, es_VE)
et (et_EE)
fa (fa_IR)
fa_AF
fi (fi_FI)
fil (fil_PH)
fo (fo_FO)
fr (fr_BE, fr_BF, fr_BI, fr_BJ, fr_BL, fr_CD, fr_CF, fr_CG, fr_CH, fr_CI, fr_CM, fr_DJ, fr_FR, fr_GA, fr_GN, fr_GP, fr_GQ, fr_KM, fr_LU, fr_MC, fr_MF, fr_MG, fr_ML, fr_MQ, fr_NE, fr_RE, fr_RW, fr_SN, fr_TD, fr_TG)
fr_CA
gu (gu_IN)
ha (ha_Latn, ha_Latn_GH, ha_Latn_NE, ha_Latn_NG)
haw (haw_US)
he (he_IL)
hi (hi_IN)
hr (hr_HR)
hu (hu_HU)
hy (hy_AM)
ig (ig_NG)
is (is_IS)
ja (ja_JP)
kk (kk_KZ)
kl (kl_GL)
km (km_KH)
kn (kn_IN)
ko (ko_KR)
kok (kok_IN)
ln (ln_CD, ln_CG)
lt (lt_LT)
lv (lv_LV)
mk (mk_MK)
ml (ml_IN)
mr (mr_IN)
mt (mt_MT)
my (my_MM)
nb (nb_NO)
nn (nn_NO)
nso (nso_ZA)
om (om_ET, om_KE)
or (or_IN)
pa (pa_Arab, pa_Arab_PK, pa_Guru, pa_Guru_IN)
pl (pl_PL)
ps (ps_AF)
ro (ro_RO, ro_MD)
root (chr, chr_US, ga, ga_IE, id, id_ID, it, it_CH, it_IT, ka, ka_GE, ky, ky_KG, ms, ms_BN, ms_MY, nl, nl_AW, nl_BE, nl_CW, nl_NL, nl_SX, pt, pt_AO, pt_BR, pt_GW, pt_MZ, pt_PT, pt_ST, st, st_LS, st_ZA, sw, sw_KE, sw_TZ, xh, xh_ZA, zu, zu_ZA)
ru (ru_MD, ru_RU, ru_UA)
se (se_FI, se_NO)
si (si_LK)
sk (sk_SK)
sl (sl_SI)
sq (sq_AL)
sr (sr_Cyrl, sr_Cyrl_BA, sr_Cyrl_ME, sr_Cyrl_RS)
sr_Latn (sr_Latn_RS, sr_Latn_BA, sr_Latn_ME)
sv (sv_FI, sv_SE)
ta (ta_IN, ta_LK)
te (te_IN)
th (th_TH)
tn (tn_ZA)
to (to_TO)
tr (tr_TR)
uk (uk_UA)
ur (ur_PK, ur_IN)
vi (vi_VN)
wae (wae_CH)
yo (yo_NG)
zh (zh_Hans, zh_Hans_CN, zh_Hans_SG)
zh_Hant (zh_Hant_HK, zh_Hant_MO, zh_Hant_TW)

You can see the base locale in the filename, e.g. de.xml, when you go inside the file, you fined an element like this one:

<collations validSubLocales="de_AT de_BE de_CH de_DE de_LI de_LU">

which lists additional Sublocales. Script and Territory is available in the file as well.

It takes some time until the CLDR data comes into Intl (C) which then is bind against PHP Intl extension. So cross check with the Intl library version / binding on your system. Just in case it differs a bit from your installation.

Get default locale for language in PHP

Having thought more about the problem and the particular setup I have, I came up with this solution, which seems to work. Note that I don't have control over what languages I need to support: there are translation files dropped into a predefined place and system locales installed by someone else. During runtime, I need to support a particular language if corresponding translation file exists and and system locale is installed. This got me to this solution:

function getLocale($lang)
{
    $locs = array();
    exec('locale -a', $locs);

    $locale = 'en_GB';
    foreach($locs as $l)
    {
        $regex = "/$lang\_[A-Z]{2}$/";
        if(preg_match($regex, $l) && file_exists(TRANSROOT . "/$lang.php"))
        {
            $locale = $l;
            break;
        }
    }

    return $locale;
}

I'm defaulting to en_GB if I cannot resolve a locale, because I know for certain that en_GB is installed (we're located in the UK as are our servers).

How to pass list of existing locales into dropdown menu

If you have multiple locales defined in config/app.php, like described here:

'locales' => ['en' => 'English', 'sv' => 'Swedish'],

You could try to do this:

{!! Form::select('language', array_flip(config('app.locales')), null, ['placeholder' => 'Pick a language']) !!}

config() will get locales list and array_flip() will swap keys and values for Form::select.

Google App engine: List of available locales for PHP

Google App Engine supports only standard "C" locale.

PHP: Where does setlocale's Value Come From?

It appears that PHP is picking these values up directly from the shell's environment, and that the value for LC_CTYPE will also check LANG's value

% cat test.php
<?php
echo setlocale(LC_ALL, 0),"\n";

% echo $LANG
en_US.UTF-8

% echo $LC_CTYPE

% php test.php
C/en_US.UTF-8/C/C/C/C

% LC_CTYPE=C php test.php
C

% LANG=C php test.php
C

% LANG=C LC_CTYPE=en_US.UTF-8 php test.php
C/en_US.UTF-8/C/C/C/C

So, MacOS appears to set LANG to en_US.UTF-8 for a user's personal shell. My presumption is when I'm starting my php-fpm instance via

brew services start php

that the -- LaunchAgent? -- is using a shell where LANG or LC_CTYPE is set to C -- presumably because only humans are interesting in seeing things formatted as UTF-8.