Czech (Czech Republic) (cs-CZ)

Complete reference for the cs-CZ locale — live Intl API output, CLDR plural rules, and framework config snippets.

Locale reference

Czech (Czech Republic)

Locale metadata

BCP 47 codecs-CZ

Native nameČeština (Česká republika)

English nameCzech (Czech Republic)

Languagecs

RegionCZ

ScriptLatn

Text directionLeft-to-right (LTR)

CLDR plural categoriesone, few, many, other

Estimated speakers~10,000,000

Intl API Live Output

DateTimeFormat

Short18.10.26

Medium18. 10. 2026

Long18. října 2026

Fullneděle 18. října 2026

NumberFormat

Decimal1 234 567,89

Currency (USD)9,99 US$

Percent75 %

Compact1,2 mil.

RelativeTimeFormat

před 3 dny

Output for: -3 days ago

ListFormat

apples, oranges a bananas

Conjunction list: apples, oranges, bananas

CLDR Plural Rules

Categories supported by cs-CZ: one, few, many, other

oneExample number: 1

→ one

fewExample number: 3

→ few

manyExample number: 11

→ other

otherExample number: 100

→ other

Framework Config Snippets

next-intl

// next-intl configuration
// next.config.ts
import createNextIntlPlugin from 'next-intl/plugin';
const withNextIntl = createNextIntlPlugin();
export default withNextIntl({});

// i18n/routing.ts
import { defineRouting } from 'next-intl/routing';
export const routing = defineRouting({
  locales: ['cs-CZ', 'en'],
  defaultLocale: 'en',
});

react-intl

// react-intl configuration
import { IntlProvider } from 'react-intl';
import messages from './messages/cs-CZ.json';

function App() {
  return (
    <IntlProvider locale="cs-CZ" messages={messages}>
      {/* your app */}
    </IntlProvider>
  );
}

i18next

// i18next configuration
import i18n from 'i18next';
import { initReactI18next } from 'react-i18next';

i18n
  .use(initReactI18next)
  .init({
    lng: 'cs-CZ',
    fallbackLng: 'en',
    resources: {
      'cs-CZ': {
        translation: require('./locales/cs-CZ/translation.json'),
      },
    },
  });

export default i18n;