# API keys, limits and errors

Everything a developer needs on the first day with the API, in one page.

## How do I get an SMS Nitro API key?

Top up once, open the API section of the dashboard and create a key. Keys can be rotated at any time; the old one stops working immediately. Use it as a bearer token on the REST API or as the api_key parameter on the SMS-Activate-compatible endpoint.

## Limits

- Buying: up to 500 purchases per minute per account, across REST and handler_api; REST also caps purchases at 500 per minute per IP.
- Resending an SMS: up to 30 requests per minute per IP. Polling an order every few seconds is fine.
- Each account has one active key; generating a new one in the dashboard revokes the old one.

## Common responses

- NO_NUMBERS: no number was returned for that service and country on this call; retry or try another country.
- NO_BALANCE: top up; the frozen amount for active numbers counts against the balance.
- BAD_KEY: the key was rotated or is malformed.
- STATUS_WAIT_CODE / STATUS_OK: waiting for the SMS / SMS delivered (compatible endpoint).

## FAQ

**Is there a webhook?** Not for SMS. Poll the order status (every few seconds is fine within the rate limit) and read the SMS text as soon as it arrives.

Source: https://smsnitro.com/help/api-keys-and-limits