What does a 401 Unauthorized error mean?

A 401 Unauthorized response indicates that the 101domain API was unable to verify your identity. This is strictly an authentication issue, the server received your request but doesn't know who you are.

Common Causes & Solutions

If you are seeing this error, please run through the following checklist:

• Check the Header Format
  Ensure your request includes the Authorization header and uses the Bearer prefix correctly.

  • Correct: Authorization: Bearer YOUR_API_KEY

  • Incorrect: Authorization: YOUR_API_KEY (Missing Bearer prefix)

• Verify Key Expiration
  Check the expiry of our API Key. If your key has expired, it will return a 401 error. You will need to generate a new key, follow the steps in How to Get API Keys.

• Whitespace and Special Characters
  Ensure no extra spaces or hidden characters were included when copying/pasting the key into your environment variables or code.

• Malformed Keys
  If the key string itself is altered (even by one character), the hash will not match, and access will be denied. If did not copy this key into a secure password manager, you may need to generate a new key.

Examples of a 401 Unauthorized errors

Bad Request Example (Missing or Invalid Token)

GET /v1/account/balance HTTP/1.1
Host: api.101domain.com
Authorization: Bearer invalid_or_expired_key_123

Response (401 Unauthorized):

{
  "status": "error",
  "code": "UNAUTHORIZED",
  "message": "Bearer token is missing, invalid, or expired.",
  "errors": null
}

How to Fix a 401 Unauthorized Error

1. Log into your 101domain account and check if the key status you are using is Active.

   1. If the key is active but still failing, revoke it and generate a new key. This is often the fastest resolution.

2. Run a simple test in your terminal using Test with cURL to rule out code-specific issues:

curl -X GET "https://api.101domain.com/v1/account/balance" 
-H "Authorization: Bearer YOUR_API_KEY"