err:unkey:authentication:malformed

{
  "meta": {
    "requestId": "req_2c9a0jf23l4k567"
  },
  "error": {
    "detail": "Authentication credentials were incorrectly formatted",
    "status": 401,
    "title": "Unauthorized",
    "type": "https://unkey.com/docs/api-reference/errors-v2/unkey/authentication/malformed"
  }
}

​

What Happened?

This error occurs when your request includes authentication credentials, but they are not formatted correctly. The Unkey API expects API keys to be provided in a specific format in the Authorization header.

Common causes include:

• Missing the “Bearer” prefix before your API key
• Including extra spaces or characters
• Using incorrect casing (e.g., “bearer” instead of “Bearer”)
• Providing a malformed or truncated API key

Here’s an example of a request with incorrectly formatted credentials:

# Missing the "Bearer" prefix
curl -X POST https://api.unkey.com/v1/keys.listKeys \
  -H "Content-Type: application/json" \
  -H "Authorization: unkey_YOUR_API_KEY"

​

How To Fix

To fix this error, ensure your Authorization header follows the correct format:

1. Use the correct format: Ensure your Authorization header follows the format Bearer unkey_YOUR_API_KEY
2. Check for extra spaces or characters: Make sure there are no invisible characters or line breaks
3. Verify the API key format: Your Unkey API key should start with unkey_

Here’s the correctly formatted request:

curl -X POST https://api.unkey.com/v1/keys.listKeys \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer unkey_YOUR_API_KEY"

When properly authenticated, you’ll receive a successful response like this:

{
  "meta": {
    "requestId": "req_8f7g6h5j4k3l2m1n"
  },
  "data": {
    "keys": [
      {
        "keyId": "key_123abc456def",
        "name": "Production API Key"
      }
    ]
  }
}

​

Common Mistakes

• Authorization header format: Must be exactly Bearer unkey_YOUR_API_KEY with a single space after “Bearer”
• Incorrect casing: Using “bearer” instead of “Bearer”
• API key format: Your Unkey API key should start with unkey_ and contain no spaces
• Using wrong key type: Ensure you’re using a root key for management API calls
• Copying errors: Check for invisible characters or line breaks that might have been copied
• Extra characters: Including quotes or other characters around the API key
• Truncated keys: Accidentally cutting off part of the API key when copying

​

Related Errors

• err:unkey:authentication:missing - When no authentication credentials are provided
• err:unkey:authentication:key_not_found - When the provided API key doesn’t exist