How to extract last X digits from fixed Y digit number using RegEx?

Question

How to extract last X digits from fixed Y digit number using RegEx?

input : 1234567890123456

• ((?=\d{16}$)\d{10}|) gives 1234567890

But

• ((?=\d{16}$)\d{10}$|) does not give 7890123456

basically, I want last 10 digits if it is compulsory 16 digit no else nothing.

Answer 1

Looks like you're not using Java and cannot use capture groups.

For your tibco tool you can use this regex with validation of 16 digits to grab last 10 digits:

(?<=^\d{6})\d{10}$

RegEx Demo

RegEx Breakup:

• (?<=^\d{6}) is a positive lookbehind to assert that we have 6 digits from start to previous position
• \d{10}$ matched 10 digits at the end of string