Regex for Step by Step Ip Check

ip_regex

/^((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\.((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\.((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\.(1?\d?\d|25[0-5]?|2[0-4]?\d?)?)?)?)?)?)?)?$/

ip_v6_regex

/^(([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{0,4})?)?)?)?)?)?)?)?)?)?)?)?)?)?)|[\da-fA-F]{0,4}:(:[\da-fA-F]{0,4})?)?$/

ip_v6_with_netmask_regex

/^(([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(:([\da-fA-F]{1,4}(\/(\d\d?|1[01]\d|12[0-8])?)?)?)?)?)?)?)?)?)?)?)?)?)?)?)?)|[\da-fA-F]{0,4}:(:[\da-fA-F]{0,4})?(\/(\d\d?|1[01]\d|12[0-8])?)?)?$/

ip_w_optional_netmask_for_mysql

^([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(\/([0-2][0-9]|3[0-2]))?$

ip_with_netmask_regex

/^((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\.((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\.((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\.((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\/([12]?\d|3[12])?)?)?)?)?)?)?)?)?$/

regex_step_by_step_checker_example.html

<script>
  var prevValue = '';
  function onKeyUp(e){
    var regex = /^((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\.((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\.((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\.((1?\d?\d|25[0-5]?|2[0-4]?\d?)(\/([12]?\d|3[12])?)?)?)?)?)?)?)?)?$/;

    if(!regex.test(e.target.value))
        e.target.value = prevValue;
    else prevValue = e.target.value;
  }
</script>
<input type="text" onkeyup="onKeyUp(event)" />