---
title: React SDK
---

# React SDK

Official React component + hook for CaptchaLa CAPTCHA — published as [`@captcha-la/react`](https://www.npmjs.com/package/@captcha-la/react).

## Live demo

::: tip 📦
[demo-v1.captcha.la/react](https://demo-v1.captcha.la/react/) — runnable demo with all four product modes.
Source: [Captcha-La/react-example](https://github.com/Captcha-La/react-example).
:::

## Install

```bash
npm install @captcha-la/react
# or
yarn add @captcha-la/react
# or
pnpm add @captcha-la/react
```

Peer dependencies: `react@^17 || ^18 || ^19`, `react-dom@^17 || ^18 || ^19`.

## Quick start

### Component

```tsx
import { Captchala } from '@captcha-la/react'

function App() {
  return (
    <Captchala
      appKey="your-app-key"
      product="popup"
      onSuccess={(result) => console.log('pass_token:', result.token)}
      onError={(err) => console.error(err)}
    />
  )
}
```

### Hook

```tsx
import { useCaptchala } from '@captcha-la/react'

function LoginForm() {
  const { ready, verify } = useCaptchala({
    appKey: 'your-app-key',
    product: 'bind',
    action: 'login',
  })

  async function handleSubmit(e) {
    e.preventDefault()
    const result = await verify()
    // result.token → submit with the form
  }

  return (
    <form onSubmit={handleSubmit}>
      <button type="submit" disabled={!ready}>Login</button>
    </form>
  )
}
```

## Props

| Prop | Type | Default | Description |
|------|------|---------|-------------|
| `appKey` | `string` | *required* | CaptchaLa application key |
| `serverToken` | `string` | - | One-time, server-issued challenge token. Required when the app has `server_token_required=true`. |
| `product` | `'popup' \| 'float' \| 'embed' \| 'bind'` | `'popup'` | Display mode |
| `action` | `string` | `'default'` | Action identifier |
| `lang` | `string` | `'zh-CN'` | Language code |
| `onSuccess` | `(result) => void` | - | Success callback |
| `onError` | `(error) => void` | - | Error callback |
| `onClose` | `() => void` | - | Close callback |
| `onReady` | `() => void` | - | Ready callback |
| `className` | `string` | - | Container class name |
| `style` | `CSSProperties` | - | Container inline styles |

## Methods (via `ref`)

```tsx
import { useRef } from 'react'
import { Captchala, type CaptchalaRef } from '@captcha-la/react'

function App() {
  const ref = useRef<CaptchalaRef>(null)
  return (
    <>
      <Captchala ref={ref} appKey="your-app-key" />
      <button onClick={() => ref.current?.verify()}>Verify</button>
    </>
  )
}
```

| Method | Description |
|--------|-------------|
| `verify()` | Trigger verification |
| `reset()` | Reset CAPTCHA state |
| `destroy()` | Destroy the instance |
| `bindTo(selector)` | Bind to element (for `bind` mode) |
| `setLang(lang)` | Switch language in place |

## Production: `serverToken` mode

```tsx
import { useState, useEffect } from 'react'
import { Captchala } from '@captcha-la/react'

function LoginPage() {
  const [token, setToken] = useState<string>()

  useEffect(() => {
    fetch('/api/captcha-token')         // your own backend
      .then((r) => r.json())
      .then((d) => setToken(d.server_token))
  }, [])

  if (!token) return <div>Loading…</div>

  return (
    <Captchala
      serverToken={token}
      appKey="pk_your_public_app_key"
      action="login"
      onSuccess={(r) => console.log('pass_token:', r.token)}
    />
  )
}
```

See [API Reference](/api-reference) for the full backend contract.

## Links

- [npm](https://www.npmjs.com/package/@captcha-la/react) · [GitHub](https://github.com/Captcha-La/react) · [example](https://github.com/Captcha-La/react-example)
- [Web SDK overview](/web-sdk) · [API Reference](/api-reference)