API reference

New in 0.3: a framework-agnostic engine (bhasha-js/vanilla), a server-safe entry (bhasha-js/server) for React Server Components / Next.js App Router, and a npx bhasha pull CLI that makes t() type-safe (autocomplete + a compile error on a typo'd key).

<I18nProvider>

Top-level provider. Wrap your app once.

useTranslation()

const {
  t,                  // (key, params?) => string
  currentLang,        // "hi"
  setLang,            // (lang: string) => void
  supportedLangs,     // string[]
  isLoading,          // boolean
  error,              // string | null — surfaces auth/network errors
  register,           // "default" | "formal" | "casual"
  setRegister,        // (register) => void
  setSegment,         // (segment: string) => void
  formatNumber,       // (value, options?) => string
  formatCurrency,     // (value, options?) => string
  formatDate,         // (date, options?) => string
  formatPhonetic,     // (key) => string  — IPA (needs voice:true)
  formatSSML,         // (key) => string  — SSML (needs voice:true)
} = useTranslation();

t(key, params?)

The translation function. Returns the translated string for the current language with fallback chain support.

t("hero.title");                              // simple lookup
t("greeting", { name: "Rohan" });              // interpolation
t("items", { count: 5 });                       // pluralization (uses items_one / items_other)

setLang(lang)

Switch the active language. Triggers font load + RTL switch + re-render.

useLangInfo()

const {
  code,            // "hi"
  name,            // "हिन्दी"
  englishName,     // "Hindi"
  dir,             // "ltr" | "rtl"
  font,            // "Noto Sans Devanagari, sans-serif"
  script,          // "Devanagari"
  defaultRegion,   // "IN"
  intlLocale,      // "hi-IN"
  defaultCurrency, // "INR"
} = useLangInfo();

<LanguageSwitcher />

<Trans />

Component-based translation, useful when wrapping rendered output.

<Trans id="hero.title" />
<Trans id="greeting" params={{ name: "Rohan" }} as="h1" />

Standalone utilities

These don't need React. Import directly.

formatNumber(value, lang, region?, options?)

formatCurrency(value, lang, region?, options?)

formatDate(date, lang, region?, options?)

getPluralCategory(count, lang)

Returns "one" or "other" based on the language's CLDR plural rules.

getPluralCategory(0, "hi");   // "one"   (Hindi: 0 is singular)
getPluralCategory(0, "en");   // "other" (English: 0 is plural)
getPluralCategory(1, "ta");   // "one"

getFallbackChain(lang)

Returns the culturally-aware fallback chain for the language.

getFallbackChain("bn");   // ["bn", "hi", "en"]
getFallbackChain("ta");   // ["ta", "en"] (Dravidian — skips Hindi)
getFallbackChain("pa-PK");// ["pa-PK", "ur", "en"]

getLangInfo(lang), LANGUAGES, REGION_OVERRIDES

Read-only access to the language metadata database.

Public SDK API