> For the complete documentation index, see [llms.txt](https://docs.stopbot.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.stopbot.net/v2/api-v2-documentation/authentication.md).

# Authentication

Authentication is used across all endpoints, including Account, Blocker, Blocker V2, SmartURLs, IP Lookup, Email Validation, and Phone Number Identify.

### API Key Parameter

Send your API key using the `apikey` query parameter.

```
apikey={API_KEY}
```

Example:

```
https://api.stopbot.net/services/account?apikey={API_KEY}
```

### Authenticated Request Examples

Account:

```bash
curl "https://api.stopbot.net/services/account?apikey={API_KEY}"
```

IP Lookup:

```bash
curl "https://api.stopbot.net/services/iplookup?apikey={API_KEY}&ip=1.1.1.1"
```

Blocker:

```bash
curl "https://api.stopbot.net/services/blocker?apikey={API_KEY}&ip=1.1.1.1&ua={USER_AGENT}&url={URL}"
```

SmartURLs:

```bash
curl "https://api.stopbot.net/services/shorterlink?apikey={API_KEY}&ip=1.1.1.1&keyname={KEYNAME}&ua={USER_AGENT}&url={URL}"
```

### API Key Format

API keys must use alphanumeric characters.

```
A-Z a-z 0-9
```

Use the full API key exactly as provided in the STOPBOT panel.

### Security Recommendations

* Keep your API key on the server side.
* Do not expose your API key in browser-only JavaScript.
* Do not commit your API key to public repositories.
* Do not place your API key in mobile app bundles.
* Rotate your API key if it has been exposed.
* Use environment variables or server-side configuration for production.

### Common Authentication Errors

Invalid API key format:

```json
{
  "errorMessage": "Apikey format is invalid.",
  "status": "failed"
}
```

API key not found:

```json
{
  "status": "failed",
  "errorMessage": "API key not found. Please check your API key or create a new one."
}
```

### Authenticated Access Errors

These errors can appear after an API key is recognized, but the request cannot continue because account access is not available.

Subscription expired or quota limit reached:

```json
{
  "status": "failed",
  "errorMessage": "Please increase your quota or extend the duration of your API key."
}
```

### Next Step

After your API key is ready, continue to the endpoint that matches your integration needs.