regex to detect ip address code example

Example 1: regex ip address

^((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$

Example 2: regex check is valid ip

((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)(\.|$)){4}

Example 3: regex check is valid ip

"((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)(\.|$)){4}"