Wildcards, also known as asterisks (*) in robots.txt, can be used to match patterns in URL paths. Here are the steps to use them:
- Identify the specific portions of the URL path where you want to use wildcards. For example, you might want to disallow all URLs under a specific directory.
- Determine the level of specificity needed for the wildcard. There are two types of wildcards that can be used:
Use a leading wildcard () in the path to match any sequence of characters. For example, Disallow: /example// would match /example/abc/ and /example/123/, but not /example/.
Use a trailing wildcard ($) in the path to match any characters at the end of the URL path. For example, Disallow: /example/$/ would match /example/ and /example/abc/, but not /example/abc/123/.
- Add the appropriate wildcard in the robots.txt file. Here's an example:
In this example, any URL path starting with /example/ followed by any sequence of characters will be disallowed for all user agents.
- Test the robots.txt file using Google's robots.txt Tester tool or similar tools to ensure it works as intended. This will allow you to check if the wildcards are functioning correctly and if any syntax errors are present.
Remember to always double-check and thoroughly test the robots.txt file to make sure it blocks the desired URLs while allowing access to the necessary ones. Be cautious while using wildcards, as they can have unintended consequences if used improperly.