regular expression

Regular expression online test

Common regular expressions

• IPv4 check

^((2(5[0-5]|[0-4]\d))|[0-1]?\d{
    1,2})(\.((2(5[0-5]|[0-4]\d))|[0-1]?\d{
    1,2})){
    3}$

• IPv6 check

^\s*((([0-9A-Fa-f]{
    1,4}:){
    7}([0-9A-Fa-f]{
    1,4}|:))|(([0-9A-Fa-f]{
    1,4}:){
    6}(:[0-9A-Fa-f]{
    1,4}|((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){
    3})|:))|(([0-9A-Fa-f]{
    1,4}:){
    5}(((:[0-9A-Fa-f]{
    1,4}){
    1,2})|:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){
    3})|:))|(([0-9A-Fa-f]{
    1,4}:){
    4}(((:[0-9A-Fa-f]{
    1,4}){
    1,3})|((:[0-9A-Fa-f]{
    1,4})?:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){
    3}))|:))|(([0-9A-Fa-f]{
    1,4}:){
    3}(((:[0-9A-Fa-f]{
    1,4}){
    1,4})|((:[0-9A-Fa-f]{
    1,4}){
    0,2}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){
    3}))|:))|(([0-9A-Fa-f]{
    1,4}:){
    2}(((:[0-9A-Fa-f]{
    1,4}){
    1,5})|((:[0-9A-Fa-f]{
    1,4}){
    0,3}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){
    3}))|:))|(([0-9A-Fa-f]{
    1,4}:){
    1}(((:[0-9A-Fa-f]{
    1,4}){
    1,6})|((:[0-9A-Fa-f]{
    1,4}){
    0,4}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){
    3}))|:))|(:(((:[0-9A-Fa-f]{
    1,4}){
    1,7})|((:[0-9A-Fa-f]{
    1,4}){
    0,5}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){
    3}))|:)))(%.+)?\s*$

Can match IPV6 Address
fe80:0000:0000:0000:0204:61ff:fe9d:f156 // full form of IPv6
fe80:0:0:0:204:61ff:fe9d:f156 // drop leading zeroes
fe80::204:61ff:fe9d:f156 // collapse multiple zeroes to :: in the IPv6 address
fe80:0000:0000:0000:0204:61ff:254.157.241.86 // IPv4 dotted quad at the end
fe80:0:0:0:0204:61ff:254.157.241.86 // drop leading zeroes, IPv4 dotted quad at the end
fe80::204:61ff:254.157.241.86 // dotted quad at the end, multiple zeroes collapsed
::1 // localhost
fe80:: // link-local prefix
2001:: // global unicast prefix