Perform Basic Authentication using cURL with Examples

There are two ways in which you can perform basic auth using cURL,

1. Using the -u or --user option
2. Using the Authorization header in the request

Using the -u or --user option

In other to perform Basic Authentication using cURL command make use of -u or the --user option followed by user:password along with the cURL command request.

Syntax:

curl -u <user-name:password> the-url

Example:

% curl -u newuser:mypassword https://example.org

Note: If your username or password contains special characters, make sure the wrap the 'user:password' within single quotes.

Example: Basic Auth cURL with special character is user or password

% curl -u 'new_user:my$password' https://example.org

Note: As the colon is used as a separator to distinguish the username and password, you cannot have a colon as a character in the username, but you can have it in the password string.

If you do not provide the password with the -u option and just provide the user, cURL will prompt you to enter the password.

Example: cURL Basic Auth with password prompt

% curl -u newuser https://example.org 
Enter host password for user 'newuser':

Perform Basic Auth by passing Authorization Header in cURL Request

The username:password string needs to be Base64-Encoded and passed in as a Header to your cURL request as below,

Plan text user:password

myuser:my$password

Base64 Encoded user:password

bXl1c2VyOm15JHBhc3N3b3Jk

cURL Example using Authorization Header

curl 'https://example.org' \
--header 'Authorization: Basic bXl1c2VyOm15JHBhc3N3b3Jk