# Authentication

The API currently supports service token based authentication. This can be sent as a query parameter named `auth`, or as an HTTP header with the same name.


```
# Token in http header (recommended)
curl -X GET https://api.rm.smartsheet.com/api/v1/users \
  -H "Content-Type: application/json"
  -H "auth: TOKEN"

# Token on URL
curl -X GET https://api.rm.smartsheet.com/api/v1/users?auth=URL-ENCODED-TOKEN \
  -H "Content-Type: application/json"
```