Different MAC Addresses Regex

Question

What is the correct regular expression for matching MAC addresses ? I googled about that but, most of questions and answers are incomplete. They only provide a regular expre

Answer 1

Why so much code? Here is how you can "normalize" your mac address:

mac.replaceAll("[^a-fA-F0-9]", "");

And here is a way to validate it:

public boolean validate(String mac) {
   Pattern p = Pattern.compile("^([a-fA-F0-9][:-]){5}[a-fA-F0-9][:-]$");
   Matcher m = p.matcher(mac);
   return m.find();
}

Answer 2

I know this question is kind of old but i think there is not a really good solution for the problem:

Two steps to do

1. Change the Mac String to parse to the format of your choice (e.g. xx:xx:xx:xx:xx:xx)
2. Write a method which validates a string with the format above

---

Example:

1)

you can easily achieve this by calling

public static String parseMac(String mac) {
    mac = mac.replaceAll("[:.-]", "");

    String res = "";
    for (int i = 0; i < 6; i++) {
        if (i != 5) {
            res += mac.substring(i * 2, (i + 1) * 2) + ":";
        } else {
            res += mac.substring(i * 2);
        }
    }
    return res;
}

:.- are the chars which will be removed from the string

2)

public static boolean isMacValid(String mac) {
    Pattern p = Pattern.compile("^([a-fA-F0-9]{2}[:-]){5}[a-fA-F0-9]{2}$");
    Matcher m = p.matcher(mac);
    return m.find();
}

Ofc you can make the Pattern a local class variable to improve the efficiency of your code.

Answer 3

MAC Address can be validated with the below code:

private static final String PATTERN = "^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$";
    
private static boolean validateMAC(String mac) {
        Pattern pattern = Pattern.compile(PATTERN);
        Matcher matcher = pattern.matcher(mac);
        return matcher.matches();
    }

Answer 4

Try this, working perfect..

A MAC address is a unique identifier assigned to most network adapters or network interface cards (NICs) by the manufacturer for identification, IEEE 802 standards use 48 bites or 6 bytes to represent a MAC address. This format gives 281,474,976,710,656 possible unique MAC addresses.

IEEE 802 standards define 3 commonly used formats to print a MAC address in hexadecimal digits:

Six groups of two hexadecimal digits separated by hyphens (-), like 01-23-45-67-89-ab

Six groups of two hexadecimal digits separated by colons (:), like 01:23:45:67:89:ab

Three groups of four hexadecimal digits separated by dots (.), like 0123.4567.89ab

public boolean macValidate(String mac) {
        Pattern p = Pattern.compile("^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$");
        Matcher m = p.matcher(mac);
        return m.find();
}

Answer 5

MAC addresses can be 6 or 20 bytes (infiniband)

The correct regexp assuming the separator is : is

^([0-9A-Fa-f]{2}:){5}(([0-9A-Fa-f]{2}:){14})?([0-9A-Fa-f]{2})$

We match 5 times XX: optionally we match another 14 times XX: and we match XX

Answer 6

Below Regex Pattern will help to manage all kinds of the above listed patterns

"([MACmac]?){1}([:.-]?){1}(([0-9A-Fa-f]{2,3}[:.-]?){4,6})"

here at end i added {4,6} because some pattern as requested below is expecting the group of 3 for 4 time. else if you are looking ONLY for the default on which is usually group of 2 characters 6 times then you can use the below one.

"([MACmac]?){1}([:.-]?){1}(([0-9A-Fa-f]{2}[:.-]?){6})"

hope this helps all.