All requests to the Email Validation API must be authenticated using an API Key.
API keys identify your account, determine access permissions, and enforce rate limits.

Unauthenticated or invalid requests will always fail with:

401 Unauthorized

1. Authentication Method

Every request must include the Authorization header:

Authorization: Bearer <YOUR_API_KEY

This key must remain confidential and should only be used from your server, never in client-side code.

2. Generating API Keys

You can generate API keys directly from your dashboard.

Steps to Create an API Key

1. Log in to your account

2. Navigate to Settings → API Keys

3. Click Generate New API Key

4. Give it a meaningful name (e.g., "Production Server" or "Staging")

5. Copy the key and store it securely

⚠️ API Keys provide full access to your API usage.
Treat them like passwords — do not expose them publicly.

3. Example Authenticated Request

cURL Example

curl -X POST https://rapid-email-verifier.fly.dev/api/validate \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"email": "user@example.com"}'

{
  "success": false,
  "error": {
    "code": "UNAUTHORIZED",
    "message": "Missing or invalid API key"
  }
}

4. Rate Limits

Rate limits depend on your plan and apply per API key.

Rate Limit Error Example

{
  "success": false,
  "error": {
    "code": "RATE_LIMIT_EXCEEDED",
    "message": "Rate limit exceeded. Try again later."
  }
}

Checking balance

curl -X GET https://rapid-email-verifier.fly.dev/api/v1/credits/balance \
  -H "Authorization: Bearer YOUR_API_KEY"

Response

{
  "success": true,
  "data": {
    "balance": 9850,
    "used_today": 150,
    "plan": "starter"
  }
}