regex101: PCRE (Legacy) Match Workspace

\ban ASCII word boundary

Group 1(127\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|0?10\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|172\.0?1[6-9]\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|172\.0?2[0-9]\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|172\.0?3[01]\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|192\.168\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|169\.254\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|::1|[fF][cCdD][0-9a-fA-F]{2}(?:[:][0-9a-fA-F]{0,4}){0,7}|[fF][eE][89aAbB][0-9a-fA-F](?:[:][0-9a-fA-F]{0,4}){0,7})

1st Alternative127\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

127the literal text 127

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Non-Capturing Group(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

1st Alternative25[0-5]

25the literal text 25

Character Class[0-5]

0-5one character from 0 (48₁₀) to 5 (53₁₀)

2nd Alternative2[0-4][0-9]

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[0-4]

0-4one character from 0 (48₁₀) to 4 (52₁₀)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

3rd Alternative[01]?[0-9][0-9]?

Character Class[01]?

?matches at most one character from the set below:

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Character Class[0-9]?

?matches at most one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Non-Capturing Group(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

1st Alternative25[0-5]

25the literal text 25

Character Class[0-5]

0-5one character from 0 (48₁₀) to 5 (53₁₀)

2nd Alternative2[0-4][0-9]

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[0-4]

0-4one character from 0 (48₁₀) to 4 (52₁₀)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

3rd Alternative[01]?[0-9][0-9]?

Character Class[01]?

?matches at most one character from the set below:

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Character Class[0-9]?

?matches at most one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Non-Capturing Group(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

1st Alternative25[0-5]

25the literal text 25

Character Class[0-5]

0-5one character from 0 (48₁₀) to 5 (53₁₀)

2nd Alternative2[0-4][0-9]

3rd Alternative[01]?[0-9][0-9]?

2nd Alternative0?10\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

3rd Alternative172\.0?1[6-9]\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

4th Alternative172\.0?2[0-9]\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

5th Alternative172\.0?3[01]\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

6th Alternative192\.168\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

7th Alternative169\.254\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)

8th Alternative::1

9th Alternative[fF][cCdD][0-9a-fA-F]{2}(?:[:][0-9a-fA-F]{0,4}){0,7}

10th Alternative[fF][eE][89aAbB][0-9a-fA-F](?:[:][0-9a-fA-F]{0,4}){0,7}

Non-Capturing Group(?:\/([789]|1?[0-9]{2}))?

\ban ASCII word boundary

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Search reference

Regular Expression

\b(127\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|0?10\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|172\.0?1[6-9]\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|172\.0?2[0-9]\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|172\.0?3[01]\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|192\.168\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|169\.254\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|::1|[fF][cCdD][0-9a-fA-F]{2}(?:[:][0-9a-fA-F]{0,4}){0,7}|[fF][eE][89aAbB][0-9a-fA-F](?:[:][0-9a-fA-F]{0,4}){0,7})(?:\/([789]|1?[0-9]{2}))?\b

New

# loopback
127.0.0.0
127.0.0.0000  # only three digits supported here

# A
10.0.0.1/10
10.255.22.33

# B
172.17.100.155/32

# C
192.168.1.1
192.168.1.255

# IPv6
fc00:833e:d648:f196:5c6c:1d9a:a14b:0d59
fc01:67e5::6a66:34a7
FC02:5fcf:e093:bb10:ce77:b5c9::/112
fc03:49bd:b7c1:5685:fa0a:87e9::2/128
fc04:::2 hmpf
# Public IP addresses
0de9:b022:883f:2c3c:7dba:a184:7576:4531
04e4:e53b:0c2f:2990:27ad:0464:6dd3:b6b3
0319:3b4a:546e:d480:4814:f885:3396:bba2
5394:03f5:606f:273e:e343:d94a:610a:3f2e
63cd:ad1f:7ffb:62c7:cc17:6e20:9b59:2f7d

# More "crap"
30.168.1.255.1
127.1
192.168.1.256
-1.2.3.4
1.1.1.1.
3...3
255.255.255.255
0.0.0.0
1.1.1.01
192.99.16.30

# decimal vs. octal mix
172.032.33.33
172.033.33.33

# octal - not supported here
0254.0021.0062.0041

# link-local addresses IPv4
169.254.1.0
169.254.254.255

# link-local addresses IPv6
fe90:1234::/64
feaf:ffff::/128
febf:ffff:ffff:ffff:ffff:ffff:ffff:ffff

Regular Expressions 101

Regular Expression

Extraction