--- title: Localization description: The APIs for localizing your extension. api_version: 2025-10 api_name: checkout-ui-extensions source_url: html: https://shopify.dev/docs/api/checkout-ui-extensions/latest/apis/localization md: https://shopify.dev/docs/api/checkout-ui-extensions/latest/apis/localization.md --- # LocalizationAPI The APIs for localizing your extension. ## StandardApi The base API object provided to `purchase` extension targets. * i18n I18n required Utilities for translating content and formatting values according to the current [`localization`](https://shopify.dev/docs/api/checkout-ui-extensions/apis/localization) of the checkout. Refer to [`localization` examples](https://shopify.dev/docs/api/checkout-ui-extensions/apis/localization#examples) for more information. * localization Localization required The details about the location, language, and currency of the customer. For utilities to easily format and translate content based on these details, you can use the [`i18n`](https://shopify.dev/docs/api/checkout-ui-extensions/apis/localization#standardapi-propertydetail-i18n) object instead. ### I18n * formatCurrency Returns a localized currency value. This function behaves like the standard \`Intl.NumberFormat()\` with a style of \`currency\` applied. It uses the buyer's locale by default. ```ts (number: number | bigint, options?: { inExtensionLocale?: boolean; } & NumberFormatOptions) => string ``` * formatDate Returns a localized date value. This function behaves like the standard \`Intl.DateTimeFormatOptions()\` and uses the buyer's locale by default. Formatting options can be passed in as options. ```ts (date: Date, options?: { inExtensionLocale?: boolean; } & DateTimeFormatOptions) => string ``` * formatNumber Returns a localized number. This function behaves like the standard \`Intl.NumberFormat()\` with a style of \`decimal\` applied. It uses the buyer's locale by default. ```ts (number: number | bigint, options?: { inExtensionLocale?: boolean; } & NumberFormatOptions) => string ``` * translate Returns translated content in the buyer's locale, as supported by the extension. - \`options.count\` is a special numeric value used in pluralization. - The other option keys and values are treated as replacements for interpolation. - If the replacements are all primitives, then \`translate()\` returns a single string. - If replacements contain UI components, then \`translate()\` returns an array of elements. ```ts I18nTranslate ``` ```ts export interface I18n { /** * Returns a localized number. * * This function behaves like the standard `Intl.NumberFormat()` * with a style of `decimal` applied. It uses the buyer's locale by default. * * @param options.inExtensionLocale - if true, use the extension's locale */ formatNumber: ( number: number | bigint, options?: {inExtensionLocale?: boolean} & Intl.NumberFormatOptions, ) => string; /** * Returns a localized currency value. * * This function behaves like the standard `Intl.NumberFormat()` * with a style of `currency` applied. It uses the buyer's locale by default. * * @param options.inExtensionLocale - if true, use the extension's locale */ formatCurrency: ( number: number | bigint, options?: {inExtensionLocale?: boolean} & Intl.NumberFormatOptions, ) => string; /** * Returns a localized date value. * * This function behaves like the standard `Intl.DateTimeFormatOptions()` and uses * the buyer's locale by default. Formatting options can be passed in as * options. * * @see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat0 * @see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat#using_options * * @param options.inExtensionLocale - if true, use the extension's locale */ formatDate: ( date: Date, options?: {inExtensionLocale?: boolean} & Intl.DateTimeFormatOptions, ) => string; /** * Returns translated content in the buyer's locale, * as supported by the extension. * * - `options.count` is a special numeric value used in pluralization. * - The other option keys and values are treated as replacements for interpolation. * - If the replacements are all primitives, then `translate()` returns a single string. * - If replacements contain UI components, then `translate()` returns an array of elements. */ translate: I18nTranslate; } ``` ### I18nTranslate This returns a translated string matching a key in a locale file. ```ts export interface I18nTranslate { ( key: string, options?: Record, ): ReplacementType extends string | number ? string : (string | ReplacementType)[]; } ``` ### Localization * country The country context of the checkout. This value carries over from the context of the cart, where it was used to contextualize the storefront experience. It will update if the buyer changes the country of their shipping address. If the country is unknown, then the value is undefined. ```ts SubscribableSignalLike ``` * currency The currency that the customer sees for money amounts in the checkout. ```ts SubscribableSignalLike ``` * extensionLanguage This is the customer's language, as supported by the extension. If the customer's actual language is not supported by the extension, then this is the language that is used for translations. For example, if the customer's language is 'fr-CA' but your extension only supports translations for 'fr', then the \`isoCode\` for this language is 'fr'. If your extension does not provide french translations at all, then this value is the default locale for your extension (that is, the one matching your .default.json file). ```ts SubscribableSignalLike ``` * language The language the customer sees in the checkout. ```ts SubscribableSignalLike ``` * market The \[market]\(/docs/apps/markets) context of the checkout. This value carries over from the context of the cart, where it was used to contextualize the storefront experience. It will update if the buyer changes the country of their shipping address. If the market is unknown, then the value is undefined. > Caution: This field is deprecated and will be removed in a future version. ```ts SubscribableSignalLike ``` * timezone The buyer’s time zone. ```ts SubscribableSignalLike ``` ```ts export interface Localization { /** * The currency that the customer sees for money amounts in the checkout. */ currency: SubscribableSignalLike; /** * The buyer’s time zone. */ timezone: SubscribableSignalLike; /** * The language the customer sees in the checkout. */ language: SubscribableSignalLike; /** * This is the customer's language, as supported by the extension. * If the customer's actual language is not supported by the extension, * then this is the language that is used for translations. * * For example, if the customer's language is 'fr-CA' but your extension * only supports translations for 'fr', then the `isoCode` for this * language is 'fr'. If your extension does not provide french * translations at all, then this value is the default locale for your * extension (that is, the one matching your .default.json file). */ extensionLanguage: SubscribableSignalLike; /** * The country context of the checkout. This value carries over from the * context of the cart, where it was used to contextualize the storefront * experience. It will update if the buyer changes the country of their * shipping address. If the country is unknown, then the value is undefined. */ country: SubscribableSignalLike; /** * The [market](/docs/apps/markets) context of the * checkout. This value carries over from the context of the cart, where it * was used to contextualize the storefront experience. It will update if the * buyer changes the country of their shipping address. If the market is unknown, * then the value is undefined. * * > Caution: This field is deprecated and will be removed in a future version. * * @deprecated Deprecated as of version `2025-04` */ market: SubscribableSignalLike; } ``` ### SubscribableSignalLike Represents a read-only value managed on the main thread that an extension can subscribe to. Example: Checkout uses this to manage the state of an object and communicate state changes to extensions running in a sandboxed web worker. This interface is compatible with \[Preact's ReadonlySignal]\(https\://github.com/preactjs/signals/blob/a023a132a81bd4ba4a0bebb8cbbeffbd8c8bbafc/packages/core/src/index.ts#L700-L709). Some fields are deprecated but still supported for backwards compatibility. In version 2025-10, \[\`StatefulRemoteSubscribable\`]\(https\://github.com/Shopify/remote-dom/blob/03929aa8418a89d41d294005f219837582718df8/packages/async-subscription/src/types.ts#L17) was replaced with \`ReadonlySignalLike\`. Checkout will remove the old fields some time in the future. * current ```ts T ``` * destroy ```ts () => Promise ``` * subscribe ```ts (fn: (value: T) => void) => () => void ``` * value ```ts T ``` ```ts export interface SubscribableSignalLike extends ReadonlySignalLike { /** * @deprecated Use `.value` instead. */ readonly current: T; /** * @deprecated No longer needed. Use Preact Signal management instead. */ destroy(): Promise; } ``` ### Country * isoCode The ISO-3166-1 code for this country. ```ts CountryCode ``` ```ts export interface Country { /** * The ISO-3166-1 code for this country. * @see https://www.iso.org/iso-3166-country-codes.html */ isoCode: CountryCode; } ``` ### CountryCode ```ts 'AC' | 'AD' | 'AE' | 'AF' | 'AG' | 'AI' | 'AL' | 'AM' | 'AN' | 'AO' | 'AR' | 'AT' | 'AU' | 'AW' | 'AX' | 'AZ' | 'BA' | 'BB' | 'BD' | 'BE' | 'BF' | 'BG' | 'BH' | 'BI' | 'BJ' | 'BL' | 'BM' | 'BN' | 'BO' | 'BQ' | 'BR' | 'BS' | 'BT' | 'BV' | 'BW' | 'BY' | 'BZ' | 'CA' | 'CC' | 'CD' | 'CF' | 'CG' | 'CH' | 'CI' | 'CK' | 'CL' | 'CM' | 'CN' | 'CO' | 'CR' | 'CU' | 'CV' | 'CW' | 'CX' | 'CY' | 'CZ' | 'DE' | 'DJ' | 'DK' | 'DM' | 'DO' | 'DZ' | 'EC' | 'EE' | 'EG' | 'EH' | 'ER' | 'ES' | 'ET' | 'FI' | 'FJ' | 'FK' | 'FO' | 'FR' | 'GA' | 'GB' | 'GD' | 'GE' | 'GF' | 'GG' | 'GH' | 'GI' | 'GL' | 'GM' | 'GN' | 'GP' | 'GQ' | 'GR' | 'GS' | 'GT' | 'GW' | 'GY' | 'HK' | 'HM' | 'HN' | 'HR' | 'HT' | 'HU' | 'ID' | 'IE' | 'IL' | 'IM' | 'IN' | 'IO' | 'IQ' | 'IR' | 'IS' | 'IT' | 'JE' | 'JM' | 'JO' | 'JP' | 'KE' | 'KG' | 'KH' | 'KI' | 'KM' | 'KN' | 'KP' | 'KR' | 'KW' | 'KY' | 'KZ' | 'LA' | 'LB' | 'LC' | 'LI' | 'LK' | 'LR' | 'LS' | 'LT' | 'LU' | 'LV' | 'LY' | 'MA' | 'MC' | 'MD' | 'ME' | 'MF' | 'MG' | 'MK' | 'ML' | 'MM' | 'MN' | 'MO' | 'MQ' | 'MR' | 'MS' | 'MT' | 'MU' | 'MV' | 'MW' | 'MX' | 'MY' | 'MZ' | 'NA' | 'NC' | 'NE' | 'NF' | 'NG' | 'NI' | 'NL' | 'NO' | 'NP' | 'NR' | 'NU' | 'NZ' | 'OM' | 'PA' | 'PE' | 'PF' | 'PG' | 'PH' | 'PK' | 'PL' | 'PM' | 'PN' | 'PS' | 'PT' | 'PY' | 'QA' | 'RE' | 'RO' | 'RS' | 'RU' | 'RW' | 'SA' | 'SB' | 'SC' | 'SD' | 'SE' | 'SG' | 'SH' | 'SI' | 'SJ' | 'SK' | 'SL' | 'SM' | 'SN' | 'SO' | 'SR' | 'SS' | 'ST' | 'SV' | 'SX' | 'SY' | 'SZ' | 'TA' | 'TC' | 'TD' | 'TF' | 'TG' | 'TH' | 'TJ' | 'TK' | 'TL' | 'TM' | 'TN' | 'TO' | 'TR' | 'TT' | 'TV' | 'TW' | 'TZ' | 'UA' | 'UG' | 'UM' | 'US' | 'UY' | 'UZ' | 'VA' | 'VC' | 'VE' | 'VG' | 'VN' | 'VU' | 'WF' | 'WS' | 'XK' | 'YE' | 'YT' | 'ZA' | 'ZM' | 'ZW' | 'ZZ' ``` ### Currency * isoCode The ISO-4217 code for this currency. ```ts CurrencyCode ``` ```ts export interface Currency { /** * The ISO-4217 code for this currency. * @see https://www.iso.org/iso-4217-currency-codes.html */ isoCode: CurrencyCode; } ``` ### CurrencyCode ```ts 'AED' | 'AFN' | 'ALL' | 'AMD' | 'ANG' | 'AOA' | 'ARS' | 'AUD' | 'AWG' | 'AZN' | 'BAM' | 'BBD' | 'BDT' | 'BGN' | 'BHD' | 'BIF' | 'BMD' | 'BND' | 'BOB' | 'BOV' | 'BRL' | 'BSD' | 'BTN' | 'BWP' | 'BYN' | 'BZD' | 'CAD' | 'CDF' | 'CHE' | 'CHF' | 'CHW' | 'CLF' | 'CLP' | 'CNY' | 'COP' | 'COU' | 'CRC' | 'CUC' | 'CUP' | 'CVE' | 'CZK' | 'DJF' | 'DKK' | 'DOP' | 'DZD' | 'EGP' | 'ERN' | 'ETB' | 'EUR' | 'FJD' | 'FKP' | 'GBP' | 'GEL' | 'GHS' | 'GIP' | 'GMD' | 'GNF' | 'GTQ' | 'GYD' | 'HKD' | 'HNL' | 'HRK' | 'HTG' | 'HUF' | 'IDR' | 'ILS' | 'INR' | 'IQD' | 'IRR' | 'ISK' | 'JMD' | 'JOD' | 'JPY' | 'KES' | 'KGS' | 'KHR' | 'KMF' | 'KPW' | 'KRW' | 'KWD' | 'KYD' | 'KZT' | 'LAK' | 'LBP' | 'LKR' | 'LRD' | 'LSL' | 'LYD' | 'MAD' | 'MDL' | 'MGA' | 'MKD' | 'MMK' | 'MNT' | 'MOP' | 'MRU' | 'MUR' | 'MVR' | 'MWK' | 'MXN' | 'MXV' | 'MYR' | 'MZN' | 'NAD' | 'NGN' | 'NIO' | 'NOK' | 'NPR' | 'NZD' | 'OMR' | 'PAB' | 'PEN' | 'PGK' | 'PHP' | 'PKR' | 'PLN' | 'PYG' | 'QAR' | 'RON' | 'RSD' | 'RUB' | 'RWF' | 'SAR' | 'SBD' | 'SCR' | 'SDG' | 'SEK' | 'SGD' | 'SHP' | 'SLL' | 'SOS' | 'SRD' | 'SSP' | 'STN' | 'SVC' | 'SYP' | 'SZL' | 'THB' | 'TJS' | 'TMT' | 'TND' | 'TOP' | 'TRY' | 'TTD' | 'TWD' | 'TZS' | 'UAH' | 'UGX' | 'USD' | 'USN' | 'UYI' | 'UYU' | 'UYW' | 'UZS' | 'VES' | 'VND' | 'VUV' | 'WST' | 'XAF' | 'XAG' | 'XAU' | 'XBA' | 'XBB' | 'XBC' | 'XBD' | 'XCD' | 'XDR' | 'XOF' | 'XPD' | 'XPF' | 'XPT' | 'XSU' | 'XTS' | 'XUA' | 'XXX' | 'YER' | 'ZAR' | 'ZMW' | 'ZWL' ``` ### Language * isoCode The BCP-47 language tag. It may contain a dash followed by an ISO 3166-1 alpha-2 region code. ```ts string ``` ```ts export interface Language { /** * The BCP-47 language tag. It may contain a dash followed by an ISO 3166-1 alpha-2 region code. * * @example 'en' for English, or 'en-US' for English local to United States. * @see https://en.wikipedia.org/wiki/IETF_language_tag * @see https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 */ isoCode: string; } ``` ### Market * handle The human-readable, shop-scoped identifier for the market. ```ts string ``` * id A globally-unique identifier for a market. ```ts string ``` ```ts export interface Market { /** * A globally-unique identifier for a market. */ id: string; /** * The human-readable, shop-scoped identifier for the market. */ handle: string; } ``` ### Timezone ```ts 'Africa/Abidjan' | 'Africa/Algiers' | 'Africa/Bissau' | 'Africa/Cairo' | 'Africa/Casablanca' | 'Africa/Ceuta' | 'Africa/El_Aaiun' | 'Africa/Johannesburg' | 'Africa/Juba' | 'Africa/Khartoum' | 'Africa/Lagos' | 'Africa/Maputo' | 'Africa/Monrovia' | 'Africa/Nairobi' | 'Africa/Ndjamena' | 'Africa/Sao_Tome' | 'Africa/Tripoli' | 'Africa/Tunis' | 'Africa/Windhoek' | 'America/Adak' | 'America/Anchorage' | 'America/Araguaina' | 'America/Argentina/Buenos_Aires' | 'America/Argentina/Catamarca' | 'America/Argentina/Cordoba' | 'America/Argentina/Jujuy' | 'America/Argentina/La_Rioja' | 'America/Argentina/Mendoza' | 'America/Argentina/Rio_Gallegos' | 'America/Argentina/Salta' | 'America/Argentina/San_Juan' | 'America/Argentina/San_Luis' | 'America/Argentina/Tucuman' | 'America/Argentina/Ushuaia' | 'America/Asuncion' | 'America/Bahia' | 'America/Bahia_Banderas' | 'America/Barbados' | 'America/Belem' | 'America/Belize' | 'America/Boa_Vista' | 'America/Bogota' | 'America/Boise' | 'America/Cambridge_Bay' | 'America/Campo_Grande' | 'America/Cancun' | 'America/Caracas' | 'America/Cayenne' | 'America/Chicago' | 'America/Chihuahua' | 'America/Costa_Rica' | 'America/Cuiaba' | 'America/Danmarkshavn' | 'America/Dawson' | 'America/Dawson_Creek' | 'America/Denver' | 'America/Detroit' | 'America/Edmonton' | 'America/Eirunepe' | 'America/El_Salvador' | 'America/Fort_Nelson' | 'America/Fortaleza' | 'America/Glace_Bay' | 'America/Goose_Bay' | 'America/Grand_Turk' | 'America/Guatemala' | 'America/Guayaquil' | 'America/Guyana' | 'America/Halifax' | 'America/Havana' | 'America/Hermosillo' | 'America/Indiana/Indianapolis' | 'America/Indiana/Knox' | 'America/Indiana/Marengo' | 'America/Indiana/Petersburg' | 'America/Indiana/Tell_City' | 'America/Indiana/Vevay' | 'America/Indiana/Vincennes' | 'America/Indiana/Winamac' | 'America/Inuvik' | 'America/Iqaluit' | 'America/Jamaica' | 'America/Juneau' | 'America/Kentucky/Louisville' | 'America/Kentucky/Monticello' | 'America/La_Paz' | 'America/Lima' | 'America/Los_Angeles' | 'America/Maceio' | 'America/Managua' | 'America/Manaus' | 'America/Martinique' | 'America/Matamoros' | 'America/Mazatlan' | 'America/Menominee' | 'America/Merida' | 'America/Metlakatla' | 'America/Mexico_City' | 'America/Miquelon' | 'America/Moncton' | 'America/Monterrey' | 'America/Montevideo' | 'America/New_York' | 'America/Nipigon' | 'America/Nome' | 'America/Noronha' | 'America/North_Dakota/Beulah' | 'America/North_Dakota/Center' | 'America/North_Dakota/New_Salem' | 'America/Nuuk' | 'America/Ojinaga' | 'America/Panama' | 'America/Pangnirtung' | 'America/Paramaribo' | 'America/Phoenix' | 'America/Port-au-Prince' | 'America/Porto_Velho' | 'America/Puerto_Rico' | 'America/Punta_Arenas' | 'America/Rainy_River' | 'America/Rankin_Inlet' | 'America/Recife' | 'America/Regina' | 'America/Resolute' | 'America/Rio_Branco' | 'America/Santarem' | 'America/Santiago' | 'America/Santo_Domingo' | 'America/Sao_Paulo' | 'America/Scoresbysund' | 'America/Sitka' | 'America/St_Johns' | 'America/Swift_Current' | 'America/Tegucigalpa' | 'America/Thule' | 'America/Thunder_Bay' | 'America/Tijuana' | 'America/Toronto' | 'America/Vancouver' | 'America/Whitehorse' | 'America/Winnipeg' | 'America/Yakutat' | 'America/Yellowknife' | 'Antarctica/Casey' | 'Antarctica/Davis' | 'Antarctica/Macquarie' | 'Antarctica/Mawson' | 'Antarctica/Palmer' | 'Antarctica/Rothera' | 'Antarctica/Troll' | 'Antarctica/Vostok' | 'Asia/Almaty' | 'Asia/Amman' | 'Asia/Anadyr' | 'Asia/Aqtau' | 'Asia/Aqtobe' | 'Asia/Ashgabat' | 'Asia/Atyrau' | 'Asia/Baghdad' | 'Asia/Baku' | 'Asia/Bangkok' | 'Asia/Barnaul' | 'Asia/Beirut' | 'Asia/Bishkek' | 'Asia/Brunei' | 'Asia/Chita' | 'Asia/Choibalsan' | 'Asia/Colombo' | 'Asia/Damascus' | 'Asia/Dhaka' | 'Asia/Dili' | 'Asia/Dubai' | 'Asia/Dushanbe' | 'Asia/Famagusta' | 'Asia/Gaza' | 'Asia/Hebron' | 'Asia/Ho_Chi_Minh' | 'Asia/Hong_Kong' | 'Asia/Hovd' | 'Asia/Irkutsk' | 'Asia/Jakarta' | 'Asia/Jayapura' | 'Asia/Jerusalem' | 'Asia/Kabul' | 'Asia/Kamchatka' | 'Asia/Karachi' | 'Asia/Kathmandu' | 'Asia/Khandyga' | 'Asia/Kolkata' | 'Asia/Krasnoyarsk' | 'Asia/Kuala_Lumpur' | 'Asia/Kuching' | 'Asia/Macau' | 'Asia/Magadan' | 'Asia/Makassar' | 'Asia/Manila' | 'Asia/Nicosia' | 'Asia/Novokuznetsk' | 'Asia/Novosibirsk' | 'Asia/Omsk' | 'Asia/Oral' | 'Asia/Pontianak' | 'Asia/Pyongyang' | 'Asia/Qatar' | 'Asia/Qostanay' | 'Asia/Qyzylorda' | 'Asia/Riyadh' | 'Asia/Sakhalin' | 'Asia/Samarkand' | 'Asia/Seoul' | 'Asia/Shanghai' | 'Asia/Singapore' | 'Asia/Srednekolymsk' | 'Asia/Taipei' | 'Asia/Tashkent' | 'Asia/Tbilisi' | 'Asia/Tehran' | 'Asia/Thimphu' | 'Asia/Tokyo' | 'Asia/Tomsk' | 'Asia/Ulaanbaatar' | 'Asia/Urumqi' | 'Asia/Ust-Nera' | 'Asia/Vladivostok' | 'Asia/Yakutsk' | 'Asia/Yangon' | 'Asia/Yekaterinburg' | 'Asia/Yerevan' | 'Atlantic/Azores' | 'Atlantic/Bermuda' | 'Atlantic/Canary' | 'Atlantic/Cape_Verde' | 'Atlantic/Faroe' | 'Atlantic/Madeira' | 'Atlantic/Reykjavik' | 'Atlantic/South_Georgia' | 'Atlantic/Stanley' | 'Australia/Adelaide' | 'Australia/Brisbane' | 'Australia/Broken_Hill' | 'Australia/Darwin' | 'Australia/Eucla' | 'Australia/Hobart' | 'Australia/Lindeman' | 'Australia/Lord_Howe' | 'Australia/Melbourne' | 'Australia/Perth' | 'Australia/Sydney' | 'CET' | 'CST6CDT' | 'EET' | 'EST' | 'EST5EDT' | 'Etc/GMT' | 'Etc/GMT-1' | 'Etc/GMT-10' | 'Etc/GMT-11' | 'Etc/GMT-12' | 'Etc/GMT-13' | 'Etc/GMT-14' | 'Etc/GMT-2' | 'Etc/GMT-3' | 'Etc/GMT-4' | 'Etc/GMT-5' | 'Etc/GMT-6' | 'Etc/GMT-7' | 'Etc/GMT-8' | 'Etc/GMT-9' | 'Etc/GMT+1' | 'Etc/GMT+10' | 'Etc/GMT+11' | 'Etc/GMT+12' | 'Etc/GMT+2' | 'Etc/GMT+3' | 'Etc/GMT+4' | 'Etc/GMT+5' | 'Etc/GMT+6' | 'Etc/GMT+7' | 'Etc/GMT+8' | 'Etc/GMT+9' | 'Etc/UTC' | 'Europe/Amsterdam' | 'Europe/Andorra' | 'Europe/Astrakhan' | 'Europe/Athens' | 'Europe/Belgrade' | 'Europe/Berlin' | 'Europe/Brussels' | 'Europe/Bucharest' | 'Europe/Budapest' | 'Europe/Chisinau' | 'Europe/Copenhagen' | 'Europe/Dublin' | 'Europe/Gibraltar' | 'Europe/Helsinki' | 'Europe/Istanbul' | 'Europe/Kaliningrad' | 'Europe/Kiev' | 'Europe/Kirov' | 'Europe/Lisbon' | 'Europe/London' | 'Europe/Luxembourg' | 'Europe/Madrid' | 'Europe/Malta' | 'Europe/Minsk' | 'Europe/Monaco' | 'Europe/Moscow' | 'Europe/Oslo' | 'Europe/Paris' | 'Europe/Prague' | 'Europe/Riga' | 'Europe/Rome' | 'Europe/Samara' | 'Europe/Saratov' | 'Europe/Simferopol' | 'Europe/Sofia' | 'Europe/Stockholm' | 'Europe/Tallinn' | 'Europe/Tirane' | 'Europe/Ulyanovsk' | 'Europe/Uzhgorod' | 'Europe/Vienna' | 'Europe/Vilnius' | 'Europe/Volgograd' | 'Europe/Warsaw' | 'Europe/Zaporozhye' | 'Europe/Zurich' | 'HST' | 'Indian/Chagos' | 'Indian/Christmas' | 'Indian/Cocos' | 'Indian/Kerguelen' | 'Indian/Mahe' | 'Indian/Maldives' | 'Indian/Mauritius' | 'Indian/Reunion' | 'MET' | 'MST' | 'MST7MDT' | 'Pacific/Apia' | 'Pacific/Auckland' | 'Pacific/Bougainville' | 'Pacific/Chatham' | 'Pacific/Chuuk' | 'Pacific/Easter' | 'Pacific/Efate' | 'Pacific/Fakaofo' | 'Pacific/Fiji' | 'Pacific/Funafuti' | 'Pacific/Galapagos' | 'Pacific/Gambier' | 'Pacific/Guadalcanal' | 'Pacific/Guam' | 'Pacific/Honolulu' | 'Pacific/Kanton' | 'Pacific/Kiritimati' | 'Pacific/Kosrae' | 'Pacific/Kwajalein' | 'Pacific/Majuro' | 'Pacific/Marquesas' | 'Pacific/Nauru' | 'Pacific/Niue' | 'Pacific/Norfolk' | 'Pacific/Noumea' | 'Pacific/Pago_Pago' | 'Pacific/Palau' | 'Pacific/Pitcairn' | 'Pacific/Pohnpei' | 'Pacific/Port_Moresby' | 'Pacific/Rarotonga' | 'Pacific/Tahiti' | 'Pacific/Tarawa' | 'Pacific/Tongatapu' | 'Pacific/Wake' | 'Pacific/Wallis' | 'PST8PDT' | 'WET' ``` ## use​Currency() Returns the currency of the checkout. ### Returns * Currency ### Currency * isoCode CurrencyCode The ISO-4217 code for this currency. ### Currency * isoCode The ISO-4217 code for this currency. ```ts CurrencyCode ``` ```ts export interface Currency { /** * The ISO-4217 code for this currency. * @see https://www.iso.org/iso-4217-currency-codes.html */ isoCode: CurrencyCode; } ``` ### CurrencyCode ```ts 'AED' | 'AFN' | 'ALL' | 'AMD' | 'ANG' | 'AOA' | 'ARS' | 'AUD' | 'AWG' | 'AZN' | 'BAM' | 'BBD' | 'BDT' | 'BGN' | 'BHD' | 'BIF' | 'BMD' | 'BND' | 'BOB' | 'BOV' | 'BRL' | 'BSD' | 'BTN' | 'BWP' | 'BYN' | 'BZD' | 'CAD' | 'CDF' | 'CHE' | 'CHF' | 'CHW' | 'CLF' | 'CLP' | 'CNY' | 'COP' | 'COU' | 'CRC' | 'CUC' | 'CUP' | 'CVE' | 'CZK' | 'DJF' | 'DKK' | 'DOP' | 'DZD' | 'EGP' | 'ERN' | 'ETB' | 'EUR' | 'FJD' | 'FKP' | 'GBP' | 'GEL' | 'GHS' | 'GIP' | 'GMD' | 'GNF' | 'GTQ' | 'GYD' | 'HKD' | 'HNL' | 'HRK' | 'HTG' | 'HUF' | 'IDR' | 'ILS' | 'INR' | 'IQD' | 'IRR' | 'ISK' | 'JMD' | 'JOD' | 'JPY' | 'KES' | 'KGS' | 'KHR' | 'KMF' | 'KPW' | 'KRW' | 'KWD' | 'KYD' | 'KZT' | 'LAK' | 'LBP' | 'LKR' | 'LRD' | 'LSL' | 'LYD' | 'MAD' | 'MDL' | 'MGA' | 'MKD' | 'MMK' | 'MNT' | 'MOP' | 'MRU' | 'MUR' | 'MVR' | 'MWK' | 'MXN' | 'MXV' | 'MYR' | 'MZN' | 'NAD' | 'NGN' | 'NIO' | 'NOK' | 'NPR' | 'NZD' | 'OMR' | 'PAB' | 'PEN' | 'PGK' | 'PHP' | 'PKR' | 'PLN' | 'PYG' | 'QAR' | 'RON' | 'RSD' | 'RUB' | 'RWF' | 'SAR' | 'SBD' | 'SCR' | 'SDG' | 'SEK' | 'SGD' | 'SHP' | 'SLL' | 'SOS' | 'SRD' | 'SSP' | 'STN' | 'SVC' | 'SYP' | 'SZL' | 'THB' | 'TJS' | 'TMT' | 'TND' | 'TOP' | 'TRY' | 'TTD' | 'TWD' | 'TZS' | 'UAH' | 'UGX' | 'USD' | 'USN' | 'UYI' | 'UYU' | 'UYW' | 'UZS' | 'VES' | 'VND' | 'VUV' | 'WST' | 'XAF' | 'XAG' | 'XAU' | 'XBA' | 'XBB' | 'XBC' | 'XBD' | 'XCD' | 'XDR' | 'XOF' | 'XPD' | 'XPF' | 'XPT' | 'XSU' | 'XTS' | 'XUA' | 'XXX' | 'YER' | 'ZAR' | 'ZMW' | 'ZWL' ``` ## use​Extension​Language() Returns the buyer's language, as supported by the extension. ### Returns * Language ### Language * isoCode string The BCP-47 language tag. It may contain a dash followed by an ISO 3166-1 alpha-2 region code. ### Language * isoCode The BCP-47 language tag. It may contain a dash followed by an ISO 3166-1 alpha-2 region code. ```ts string ``` ```ts export interface Language { /** * The BCP-47 language tag. It may contain a dash followed by an ISO 3166-1 alpha-2 region code. * * @example 'en' for English, or 'en-US' for English local to United States. * @see https://en.wikipedia.org/wiki/IETF_language_tag * @see https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 */ isoCode: string; } ``` ## use​Language() Returns the current language of the checkout, and automatically re-renders your component if the language changes. ### Returns * Language ### Language * isoCode string The BCP-47 language tag. It may contain a dash followed by an ISO 3166-1 alpha-2 region code. ### Language * isoCode The BCP-47 language tag. It may contain a dash followed by an ISO 3166-1 alpha-2 region code. ```ts string ``` ```ts export interface Language { /** * The BCP-47 language tag. It may contain a dash followed by an ISO 3166-1 alpha-2 region code. * * @example 'en' for English, or 'en-US' for English local to United States. * @see https://en.wikipedia.org/wiki/IETF_language_tag * @see https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 */ isoCode: string; } ``` ## use​Localization​Country() Returns the country of the checkout, and automatically re-renders your component if the country changes. ### Returns * Country | undefined ### Country * isoCode The ISO-3166-1 code for this country. ```ts CountryCode ``` ```ts export interface Country { /** * The ISO-3166-1 code for this country. * @see https://www.iso.org/iso-3166-country-codes.html */ isoCode: CountryCode; } ``` ### CountryCode ```ts 'AC' | 'AD' | 'AE' | 'AF' | 'AG' | 'AI' | 'AL' | 'AM' | 'AN' | 'AO' | 'AR' | 'AT' | 'AU' | 'AW' | 'AX' | 'AZ' | 'BA' | 'BB' | 'BD' | 'BE' | 'BF' | 'BG' | 'BH' | 'BI' | 'BJ' | 'BL' | 'BM' | 'BN' | 'BO' | 'BQ' | 'BR' | 'BS' | 'BT' | 'BV' | 'BW' | 'BY' | 'BZ' | 'CA' | 'CC' | 'CD' | 'CF' | 'CG' | 'CH' | 'CI' | 'CK' | 'CL' | 'CM' | 'CN' | 'CO' | 'CR' | 'CU' | 'CV' | 'CW' | 'CX' | 'CY' | 'CZ' | 'DE' | 'DJ' | 'DK' | 'DM' | 'DO' | 'DZ' | 'EC' | 'EE' | 'EG' | 'EH' | 'ER' | 'ES' | 'ET' | 'FI' | 'FJ' | 'FK' | 'FO' | 'FR' | 'GA' | 'GB' | 'GD' | 'GE' | 'GF' | 'GG' | 'GH' | 'GI' | 'GL' | 'GM' | 'GN' | 'GP' | 'GQ' | 'GR' | 'GS' | 'GT' | 'GW' | 'GY' | 'HK' | 'HM' | 'HN' | 'HR' | 'HT' | 'HU' | 'ID' | 'IE' | 'IL' | 'IM' | 'IN' | 'IO' | 'IQ' | 'IR' | 'IS' | 'IT' | 'JE' | 'JM' | 'JO' | 'JP' | 'KE' | 'KG' | 'KH' | 'KI' | 'KM' | 'KN' | 'KP' | 'KR' | 'KW' | 'KY' | 'KZ' | 'LA' | 'LB' | 'LC' | 'LI' | 'LK' | 'LR' | 'LS' | 'LT' | 'LU' | 'LV' | 'LY' | 'MA' | 'MC' | 'MD' | 'ME' | 'MF' | 'MG' | 'MK' | 'ML' | 'MM' | 'MN' | 'MO' | 'MQ' | 'MR' | 'MS' | 'MT' | 'MU' | 'MV' | 'MW' | 'MX' | 'MY' | 'MZ' | 'NA' | 'NC' | 'NE' | 'NF' | 'NG' | 'NI' | 'NL' | 'NO' | 'NP' | 'NR' | 'NU' | 'NZ' | 'OM' | 'PA' | 'PE' | 'PF' | 'PG' | 'PH' | 'PK' | 'PL' | 'PM' | 'PN' | 'PS' | 'PT' | 'PY' | 'QA' | 'RE' | 'RO' | 'RS' | 'RU' | 'RW' | 'SA' | 'SB' | 'SC' | 'SD' | 'SE' | 'SG' | 'SH' | 'SI' | 'SJ' | 'SK' | 'SL' | 'SM' | 'SN' | 'SO' | 'SR' | 'SS' | 'ST' | 'SV' | 'SX' | 'SY' | 'SZ' | 'TA' | 'TC' | 'TD' | 'TF' | 'TG' | 'TH' | 'TJ' | 'TK' | 'TL' | 'TM' | 'TN' | 'TO' | 'TR' | 'TT' | 'TV' | 'TW' | 'TZ' | 'UA' | 'UG' | 'UM' | 'US' | 'UY' | 'UZ' | 'VA' | 'VC' | 'VE' | 'VG' | 'VN' | 'VU' | 'WF' | 'WS' | 'XK' | 'YE' | 'YT' | 'ZA' | 'ZM' | 'ZW' | 'ZZ' ``` ## use​Localization​Market() Returns the market of the checkout, and automatically re-renders your component if it changes. ### Returns * Market | undefined ### Market * handle The human-readable, shop-scoped identifier for the market. ```ts string ``` * id A globally-unique identifier for a market. ```ts string ``` ```ts export interface Market { /** * A globally-unique identifier for a market. */ id: string; /** * The human-readable, shop-scoped identifier for the market. */ handle: string; } ``` ## use​Timezone() Returns the time zone of the checkout, and automatically re-renders your component if the time zone changes. ### Returns * "Africa/Abidjan" | "Africa/Algiers" | "Africa/Bissau" | "Africa/Cairo" | "Africa/Casablanca" | "Africa/Ceuta" | "Africa/El\_Aaiun" | "Africa/Johannesburg" | "Africa/Juba" | "Africa/Khartoum" | "Africa/Lagos" | "Africa/Maputo" | "Africa/Monrovia" | "Africa/Nairobi" | "Africa/Ndjamena" | "Africa/Sao\_Tome" | "Africa/Tripoli" | "Africa/Tunis" | "Africa/Windhoek" | "America/Adak" | "America/Anchorage" | "America/Araguaina" | "America/Argentina/Buenos\_ ## use​Translate() Returns the `I18nTranslate` interface used to translate strings. ### Returns * I18nTranslate ### I18nTranslate ### I18nTranslate This returns a translated string matching a key in a locale file. ```ts export interface I18nTranslate { ( key: string, options?: Record, ): ReplacementType extends string | number ? string : (string | ReplacementType)[]; } ``` ### Examples * #### Translating strings ##### Description Define strings in JSON files for each locale and render them using \`translate()\`. See \[localizing UI extensions]\(/docs/apps/checkout/best-practices/localizing-ui-extensions) for more information. ##### Preact ```jsx /* See the locales/en.default.json tab for the translation keys and values for this example */ import '@shopify/ui-extensions/preact'; import {render} from 'preact'; export default function extension() { render(, document.body); } function Extension() { return ( {shopify.i18n.translate('welcomeMessage')} ); } ``` ##### locales/en.default.json ```json { "welcomeMessage": "Welcome to our store!" } ``` ## Examples Translating strings with pluralization You can use the `count` option to get a pluralized string based on the current locale. See [localizing UI extensions](https://shopify.dev/docs/apps/checkout/best-practices/localizing-ui-extensions) for more information. ### Examples * #### Translating strings with pluralization ##### Description You can use the \`count\` option to get a pluralized string based on the current locale. See \[localizing UI extensions]\(/docs/apps/checkout/best-practices/localizing-ui-extensions) for more information. ##### Preact ```jsx /* See the locales/en.default.json tab for the translation keys and values for this example */ import '@shopify/ui-extensions/preact'; import {render} from 'preact'; export default function extension() { render(, document.body); } function Extension() { const points = 10000; const formattedPoints = shopify.i18n.formatNumber(points); // Translate the loyalty points message, using pluralization to differentiate messages const loyaltyPointsMsg = shopify.i18n.translate( 'loyaltyPoints', { count: points, formattedPoints, }, ); return {loyaltyPointsMsg}; } ``` ##### locales/en.default.json ```json { "loyaltyPoints": { "one": "You have {{formattedPoints}} loyalty point", "other": "You have {{formattedPoints}} loyalty points" } } ``` ## Related [![](https://shopify.dev/images/icons/32/blocks.png)![](https://shopify.dev/images/icons/32/blocks-dark.png)](https://shopify.dev/docs/api/checkout-ui-extensions/targets) [ReferenceTargets](https://shopify.dev/docs/api/checkout-ui-extensions/targets) [![](https://shopify.dev/images/icons/32/apps.png)![](https://shopify.dev/images/icons/32/apps-dark.png)](https://shopify.dev/docs/api/checkout-ui-extensions/components) [ReferenceComponents](https://shopify.dev/docs/api/checkout-ui-extensions/components) [![](https://shopify.dev/images/icons/32/gear.png)![](https://shopify.dev/images/icons/32/gear-dark.png)](https://shopify.dev/docs/api/checkout-ui-extensions/configuration) [ReferenceConfiguration](https://shopify.dev/docs/api/checkout-ui-extensions/configuration) [![](https://shopify.dev/images/icons/32/tutorial.png)![](https://shopify.dev/images/icons/32/tutorial-dark.png)](https://shopify.dev/apps/checkout) [LearnTutorials](https://shopify.dev/apps/checkout)