# Rate Limiting & Anti-Spam
Understand the security protocols that protect your project.
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To protect your project balance and avoid spam attacks, **ReOTP** implements automatic and robust rate limiting on verification requests:
### Rate Limits
- The system automatically rejects requests if a **Phone Number** or **IP Address** exceeds **5 requests per 15 minutes**.
- When this limit is exceeded, the API responds with a 429 Too Many Requests status code.
### API Key Security
- Keep your API Key safe.
- In the dashboard, configure the Allowed Domains (Whitelisting) to ensure requests are only accepted from your verified sites and applications.