Finnish Business Id Regex

I created a regex command for checking finnish business id, it is case insensitiv

**\^(?i)(FI+:?

)(([0-9]{6,8})

([0-9]{6,7}-[0-9]{1}))$**

Valid Forms: FI:12345678 FI:1234567-8 fi:12345678 fi:1234567-8