# `RATE_LIMITED` (HTTP 429): more requests than the limit allows

The API allows 5 requests per second per key; the browser endpoint allows 20 lookups a minute per visitor.

The response carries a Retry-After header with the seconds until the window resets. The request did not run and nothing was billed.

Verifying a list one address at a time is the usual cause. The batch endpoint takes 50 addresses per request and probes them concurrently; bulk jobs take up to 100,000.

**What to do.** Wait for Retry-After, then resend. For lists, switch to the batch or bulk endpoint instead of tightening a client-side loop.

```json
{
    "success": false,
    "error": {
        "code": "RATE_LIMITED",
        "message": "Too many requests. Retry after the limit resets.",
        "request_id": "req_01m1kgdm4xngzmbmff68g94w0c"
    }
}
```

Reference: https://spaw.co/docs/errors/RATE_LIMITED