How to write Regex in Laravel

This regex should work for you: /^([a-z]){3}-([a-z]){3}-([a-z]){3}/i

For the explanation, you can look here: https://regex101.com/r/sM6wQ7/28

You can use the regex validation rule to check for this: https://laravel.com/docs/6.x/validation#rule-regex

Let me know if this works for you

I recommend using http://regexr.com to test your regular expressions.

Something like

[a-z]{3}-[a-z]{3}-[a-z]{3}

should do the trick