Regular Expressions 101

Group 1(((25[0-5])|(2[0-4]\d)|(1\d{2})|(\d{1,2}))\.){3}

{3}repeats the group contents below exactly 3 times:

Group 2((25[0-5])|(2[0-4]\d)|(1\d{2})|(\d{1,2}))

1st Alternative(25[0-5])

Group 3(25[0-5])

25the literal text 25

Character Class[0-5]

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

2nd Alternative(2[0-4]\d)

Group 4(2[0-4]\d)

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[0-4]

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

\da digit

3rd Alternative(1\d{2})

Group 5(1\d{2})

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

\d{2}a digit, repeated exactly 2 times

4th Alternative(\d{1,2})

Group 6(\d{1,2})

\d{1,2}a digit, repeated between 1 and 2 times

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 7(((25[0-5])|(2[0-4]\d)|(1\d{2})|(\d{1,2})))

Group 8((25[0-5])|(2[0-4]\d)|(1\d{2})|(\d{1,2}))

1st Alternative(25[0-5])

Group 9(25[0-5])

25the literal text 25

Character Class[0-5]

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

2nd Alternative(2[0-4]\d)

Group 10(2[0-4]\d)

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[0-4]

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

\da digit

3rd Alternative(1\d{2})

Group 11(1\d{2})

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

\d{2}a digit, repeated exactly 2 times

4th Alternative(\d{1,2})

Group 12(\d{1,2})

\d{1,2}a digit, repeated between 1 and 2 times

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

(((25[0-5])|(2[0-4]\d)|(1\d{2})|(\d{1,2}))\.){3}(((25[0-5])|(2[0-4]\d)|(1\d{2})|(\d{1,2})))

New

1.1.1.1
254.2.2.2.
255.1.1.255
256.1.1.256
012.111.111.111
12.12.12.12a
1q.1.1.1
1.1q.1.1
1.1.1q.1
1.1.1.1q
abcde254.2.2.2

Regular Expression

Extraction