Regular Expressions 101

^start of string

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

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

Group 2(1?[\d]?[\d]|2([0-4][\d]|5[0-5]))

1st Alternative1?[\d]?[\d]

1?optionally matches the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[\d]?

?matches at most one character from the set below:

\da digit

Character Class[\d]

\da digit

2nd Alternative2([0-4][\d]|5[0-5])

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Group 3([0-4][\d]|5[0-5])

1st Alternative[0-4][\d]

Character Class[0-4]

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

Character Class[\d]

\da digit

2nd Alternative5[0-5]

5the literal 5 (53₁₀ / 65₈ / 35₁₆)

Character Class[0-5]

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

Character Class[.]

.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 4(1?[\d]?[\d]|2([0-4][\d]|5[0-5]))

1st Alternative1?[\d]?[\d]

1?optionally matches the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[\d]?

?matches at most one character from the set below:

\da digit

Character Class[\d]

\da digit

2nd Alternative2([0-4][\d]|5[0-5])

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Group 5([0-4][\d]|5[0-5])

1st Alternative[0-4][\d]

Character Class[0-4]

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

Character Class[\d]

\da digit

2nd Alternative5[0-5]

5the literal 5 (53₁₀ / 65₈ / 35₁₆)

Character Class[0-5]

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

$end of string

Detailed match information will be displayed here automatically.

26 tokens

Regular Expression

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

New

10.0.0.30

Substitution

10.0.0.30