15 KiB
name, description, license
| name | description | license |
|---|---|---|
| cloudflare-turnstile | Add bot protection with Turnstile (CAPTCHA alternative). Use when: protecting forms, securing login/signup, preventing spam, migrating from reCAPTCHA, integrating with React/Next.js/Hono, implementing E2E tests, or debugging CSP errors, token validation failures, or error codes 100*/300*/600*. | MIT |
Cloudflare Turnstile
Status: Production Ready ✅ Last Updated: 2025-11-24 Dependencies: None (optional: @marsidev/react-turnstile for React) Latest Versions: @marsidev/react-turnstile@1.3.1, turnstile-types@1.2.3
Recent Updates (2025):
- March 2025: Upgraded Turnstile Analytics with TopN statistics (7 dimensions: hostnames, browsers, countries, user agents, ASNs, OS, source IPs), anomaly detection, enhanced bot behavior monitoring
- 2025: WCAG 2.1 AA compliance, Free plan (20 widgets, 7-day analytics), Enterprise features (unlimited widgets, ephemeral IDs, any hostname support, 30-day analytics, offlabel branding)
Quick Start (5 Minutes)
# 1. Create widget: https://dash.cloudflare.com/?to=/:account/turnstile
# Copy sitekey (public) and secret key (private)
# 2. Add widget to frontend
<script src="https://challenges.cloudflare.com/turnstile/v0/api.js" async defer></script>
<form>
<div class="cf-turnstile" data-sitekey="YOUR_SITE_KEY"></div>
<button type="submit">Submit</button>
</form>
# 3. Validate token server-side (Cloudflare Workers)
const formData = await request.formData()
const token = formData.get('cf-turnstile-response')
const verifyFormData = new FormData()
verifyFormData.append('secret', env.TURNSTILE_SECRET_KEY)
verifyFormData.append('response', token)
verifyFormData.append('remoteip', request.headers.get('CF-Connecting-IP'))
const result = await fetch(
'https://challenges.cloudflare.com/turnstile/v0/siteverify',
{ method: 'POST', body: verifyFormData }
)
const outcome = await result.json()
if (!outcome.success) return new Response('Invalid', { status: 401 })
CRITICAL:
- Token expires in 5 minutes, single-use only
- ALWAYS validate server-side (Siteverify API required)
- Never proxy/cache api.js (must load from Cloudflare CDN)
- Use different widgets for dev/staging/production
Rendering Modes
Implicit (auto-render on page load):
<script src="https://challenges.cloudflare.com/turnstile/v0/api.js" async defer></script>
<div class="cf-turnstile" data-sitekey="YOUR_SITE_KEY" data-callback="onSuccess"></div>
Explicit (programmatic control for SPAs):
<script src="https://challenges.cloudflare.com/turnstile/v0/api.js?render=explicit"></script>
const widgetId = turnstile.render('#container', { sitekey: 'YOUR_SITE_KEY' })
turnstile.reset(widgetId) // Reset widget
turnstile.getResponse(widgetId) // Get token
React (using @marsidev/react-turnstile):
import { Turnstile } from '@marsidev/react-turnstile'
<Turnstile siteKey={TURNSTILE_SITE_KEY} onSuccess={setToken} />
Critical Rules
Always Do
✅ Call Siteverify API - Server-side validation is mandatory
✅ Use HTTPS - Never validate over HTTP
✅ Protect secret keys - Never expose in frontend code
✅ Handle token expiration - Tokens expire after 5 minutes
✅ Implement error callbacks - Handle failures gracefully
✅ Use dummy keys for testing - Test sitekey: 1x00000000000000000000AA
✅ Set reasonable timeouts - Don't wait indefinitely for validation
✅ Validate action/hostname - Check additional fields when specified
✅ Rotate keys periodically - Use dashboard or API to rotate secrets
✅ Monitor analytics - Track solve rates and failures
Never Do
❌ Skip server validation - Client-side only = security vulnerability ❌ Proxy api.js script - Must load from Cloudflare CDN ❌ Reuse tokens - Each token is single-use only ❌ Use GET requests - Siteverify only accepts POST ❌ Expose secret key - Keep secrets in backend environment only ❌ Trust client-side validation - Tokens can be forged ❌ Cache api.js - Future updates will break your integration ❌ Use production keys in tests - Use dummy keys instead ❌ Ignore error callbacks - Always handle failures
Known Issues Prevention
This skill prevents 12 documented issues:
Issue #1: Missing Server-Side Validation
Error: Zero token validation in Turnstile Analytics dashboard Source: https://developers.cloudflare.com/turnstile/get-started/ Why It Happens: Developers only implement client-side widget, skip Siteverify call Prevention: All templates include mandatory server-side validation with Siteverify API
Issue #2: Token Expiration (5 Minutes)
Error: success: false for valid tokens submitted after delay
Source: https://developers.cloudflare.com/turnstile/get-started/server-side-validation
Why It Happens: Tokens expire 300 seconds after generation
Prevention: Templates document TTL and implement token refresh on expiration
Issue #3: Secret Key Exposed in Frontend
Error: Security bypass - attackers can validate their own tokens Source: https://developers.cloudflare.com/turnstile/get-started/server-side-validation Why It Happens: Secret key hardcoded in JavaScript or visible in source Prevention: All templates show backend-only validation with environment variables
Issue #4: GET Request to Siteverify
Error: API returns 405 Method Not Allowed Source: https://developers.cloudflare.com/turnstile/migration/recaptcha Why It Happens: reCAPTCHA supports GET, Turnstile requires POST Prevention: Templates use POST with FormData or JSON body
Issue #5: Content Security Policy Blocking
Error: Error 200500 - "Loading error: The iframe could not be loaded" Source: https://developers.cloudflare.com/turnstile/troubleshooting/client-side-errors/error-codes Why It Happens: CSP blocks challenges.cloudflare.com iframe Prevention: Skill includes CSP configuration reference and check-csp.sh script
Issue #6: Widget Crash (Error 300030)
Error: Generic client execution error for legitimate users Source: https://community.cloudflare.com/t/turnstile-is-frequently-generating-300x-errors/700903 Why It Happens: Unknown - appears to be Cloudflare-side issue (2025) Prevention: Templates implement error callbacks, retry logic, and fallback handling
Issue #7: Configuration Error (Error 600010)
Error: Widget fails with "configuration error" Source: https://community.cloudflare.com/t/repeated-cloudflare-turnstile-error-600010/644578 Why It Happens: Missing or deleted hostname in widget configuration Prevention: Templates document hostname allowlist requirement and verification steps
Issue #8: Safari 18 / macOS 15 "Hide IP" Issue
Error: Error 300010 when Safari's "Hide IP address" is enabled Source: https://community.cloudflare.com/t/turnstile-is-frequently-generating-300x-errors/700903 Why It Happens: Privacy settings interfere with challenge signals Prevention: Error handling reference documents Safari workaround (disable Hide IP)
Issue #9: Brave Browser Confetti Animation Failure
Error: Verification fails during success animation Source: https://github.com/brave/brave-browser/issues/45608 (April 2025) Why It Happens: Brave shields block animation scripts Prevention: Templates handle success before animation completes
Issue #10: Next.js + Jest Incompatibility
Error: @marsidev/react-turnstile breaks Jest tests Source: https://github.com/marsidev/react-turnstile/issues/112 (Oct 2025) Why It Happens: Module resolution issues with Jest Prevention: Testing guide includes Jest mocking patterns and dummy sitekey usage
Issue #11: localhost Not in Allowlist
Error: Error 110200 - "Unknown domain: Domain not allowed" Source: https://developers.cloudflare.com/turnstile/troubleshooting/client-side-errors/error-codes Why It Happens: Production widget used in development without localhost in allowlist Prevention: Templates use dummy test keys for dev, document localhost allowlist requirement
Issue #12: Token Reuse Attempt
Error: success: false with "token already spent" error
Source: https://developers.cloudflare.com/turnstile/troubleshooting/testing
Why It Happens: Each token can only be validated once
Prevention: Templates document single-use constraint and token refresh patterns
Configuration
wrangler.jsonc:
{
"vars": { "TURNSTILE_SITE_KEY": "1x00000000000000000000AA" },
"secrets": ["TURNSTILE_SECRET_KEY"] // Run: wrangler secret put TURNSTILE_SECRET_KEY
}
Required CSP:
<meta http-equiv="Content-Security-Policy" content="
script-src 'self' https://challenges.cloudflare.com;
frame-src 'self' https://challenges.cloudflare.com;
">
Common Patterns
Pattern 1: Hono + Cloudflare Workers
import { Hono } from 'hono'
type Bindings = {
TURNSTILE_SECRET_KEY: string
TURNSTILE_SITE_KEY: string
}
const app = new Hono<{ Bindings: Bindings }>()
app.post('/api/login', async (c) => {
const body = await c.req.formData()
const token = body.get('cf-turnstile-response')
if (!token) {
return c.text('Missing Turnstile token', 400)
}
// Validate token
const verifyFormData = new FormData()
verifyFormData.append('secret', c.env.TURNSTILE_SECRET_KEY)
verifyFormData.append('response', token.toString())
verifyFormData.append('remoteip', c.req.header('CF-Connecting-IP') || '')
const verifyResult = await fetch(
'https://challenges.cloudflare.com/turnstile/v0/siteverify',
{
method: 'POST',
body: verifyFormData,
}
)
const outcome = await verifyResult.json<{ success: boolean }>()
if (!outcome.success) {
return c.text('Invalid Turnstile token', 401)
}
// Process login
return c.json({ message: 'Login successful' })
})
export default app
When to use: API routes in Cloudflare Workers with Hono framework
Pattern 2: React + Next.js App Router
'use client'
import { Turnstile } from '@marsidev/react-turnstile'
import { useState } from 'react'
export function ContactForm() {
const [token, setToken] = useState<string>()
const [error, setError] = useState<string>()
async function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
e.preventDefault()
if (!token) {
setError('Please complete the challenge')
return
}
const formData = new FormData(e.currentTarget)
formData.append('cf-turnstile-response', token)
const response = await fetch('/api/contact', {
method: 'POST',
body: formData,
})
if (!response.ok) {
setError('Submission failed')
return
}
// Success
}
return (
<form onSubmit={handleSubmit}>
<input name="email" type="email" required />
<textarea name="message" required />
<Turnstile
siteKey={process.env.NEXT_PUBLIC_TURNSTILE_SITE_KEY!}
onSuccess={setToken}
onError={() => setError('Challenge failed')}
onExpire={() => setToken(undefined)}
/>
{error && <div className="error">{error}</div>}
<button type="submit" disabled={!token}>
Submit
</button>
</form>
)
}
When to use: Client-side forms in Next.js with React hooks
Testing Keys
Dummy Sitekeys (client):
- Always pass:
1x00000000000000000000AA - Always block:
2x00000000000000000000AB - Force interactive:
3x00000000000000000000FF
Dummy Secret Keys (server):
- Always pass:
1x0000000000000000000000000000000AA - Always fail:
2x0000000000000000000000000000000AA - Token already spent:
3x0000000000000000000000000000000AA
Bundled Resources
Scripts: check-csp.sh - Verify CSP allows Turnstile
References:
widget-configs.md- All configuration optionserror-codes.md- Error code troubleshooting (100*/200*/300*/400*/600*)testing-guide.md- Testing strategies, dummy keysreact-integration.md- React/Next.js patterns
Templates: Complete examples for Hono, React, implicit/explicit rendering, validation
Advanced Features
Pre-Clearance (SPAs): Issue cookie that persists across page navigations
turnstile.render('#container', {
sitekey: SITE_KEY,
callback: async (token) => {
await fetch('/api/pre-clearance', { method: 'POST', body: JSON.stringify({ token }) })
}
})
Custom Actions & Data: Track challenge types, pass custom data (max 255 chars)
turnstile.render('#container', {
action: 'login', // Track in analytics
cdata: JSON.stringify({ userId: '123' }), // Custom payload
})
Error Handling: Use retry: 'auto' and error-callback for resilience
turnstile.render('#container', {
retry: 'auto',
'retry-interval': 8000, // ms between retries
'error-callback': (error) => { /* handle or show fallback */ }
})
Dependencies
Required: None (loads from CDN) React: @marsidev/react-turnstile@1.3.1 (Cloudflare-recommended), turnstile-types@1.2.3 Other: vue-turnstile, ngx-turnstile, svelte-turnstile, @nuxtjs/turnstile
Official Documentation
- https://developers.cloudflare.com/turnstile/
- Use
mcp__cloudflare-docs__search_cloudflare_documentationtool
Troubleshooting
Problem: Error 110200 - "Unknown domain"
Solution: Add your domain (including localhost for dev) to widget's allowed domains in Cloudflare Dashboard. For local dev, use dummy test sitekey 1x00000000000000000000AA instead.
Problem: Error 300030 - Widget crashes for legitimate users
Solution: Implement error callback with retry logic. This is a known Cloudflare-side issue (2025). Fallback to alternative verification if retries fail.
Problem: Tokens always return success: false
Solution:
- Check token hasn't expired (5 min TTL)
- Verify secret key is correct
- Ensure token hasn't been validated before (single-use)
- Check hostname matches widget configuration
Problem: CSP blocking iframe (Error 200500)
Solution: Add CSP directives:
<meta http-equiv="Content-Security-Policy" content="
frame-src https://challenges.cloudflare.com;
script-src https://challenges.cloudflare.com;
">
Problem: Safari 18 "Hide IP" causing Error 300010
Solution: Document in error message that users should disable Safari's "Hide IP address" setting (Safari → Settings → Privacy → Hide IP address → Off)
Problem: Next.js + Jest tests failing with @marsidev/react-turnstile
Solution: Mock the Turnstile component in Jest setup:
// jest.setup.ts
jest.mock('@marsidev/react-turnstile', () => ({
Turnstile: () => <div data-testid="turnstile-mock" />,
}))
Errors Prevented: 12 documented issues (Safari 18 Hide IP, Brave confetti, Next.js Jest, CSP blocking, token reuse, expiration, hostname allowlist, widget crash 300030, config error 600010, missing validation, GET request, secret exposure)