Regex for IBAN allowing for white spaces AND checking for exact length

Question

I need to check an input field for a German IBAN. The user should be allowed to leave in white spaces and input should be validated to have a starting DE

Answer 1

Original:

^[DE]{2}([0-9a-zA-Z]{20})$

Debuggex Demo

Modified:

^DE(?:\s*[0-9a-zA-Z]\s*){20}$

Debuggex Demo