regex101: JavaScript Match Workspace

1st Alternative^(?:(?:1[6-9]|[2-9]\d)?\d{2})(?:(?:(\/|-|\.)(?:0?[13578]|1[02])\1(?:31))|(?:(\/|-|\.)(?:0?[13-9]|1[0-2])\2(?:29|30)))$

^start of line

Non-Capturing Group(?:(?:1[6-9]|[2-9]\d)?\d{2})

Non-Capturing Group(?:1[6-9]|[2-9]\d)?

?repeats the group contents below at most once:

1st Alternative1[6-9]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[6-9]

6-9one character from 6 (54₁₀) to 9 (57₁₀)

2nd Alternative[2-9]\d

Character Class[2-9]

2-9one character from 2 (50₁₀) to 9 (57₁₀)

\da digit

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

Non-Capturing Group(?:(?:(\/|-|\.)(?:0?[13578]|1[02])\1(?:31))|(?:(\/|-|\.)(?:0?[13-9]|1[0-2])\2(?:29|30)))

1st Alternative(?:(\/|-|\.)(?:0?[13578]|1[02])\1(?:31))

Non-Capturing Group(?:(\/|-|\.)(?:0?[13578]|1[02])\1(?:31))

Group 1(\/|-|\.)

1st Alternative\/

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

2nd Alternative-

-the literal - (45₁₀ / 55₈ / 2D₁₆)

3rd Alternative\.

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Non-Capturing Group(?:0?[13578]|1[02])

1st Alternative0?[13578]

0?optionally matches the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[13578]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

3the literal 3 (51₁₀ / 63₈ / 33₁₆)

5the literal 5 (53₁₀ / 65₈ / 35₁₆)

7the literal 7 (55₁₀ / 67₈ / 37₁₆)

8the literal 8 (56₁₀ / 70₈ / 38₁₆)

2nd Alternative1[02]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[02]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

\1the text saved by group 1

Non-Capturing Group(?:31)

31the literal text 31

2nd Alternative(?:(\/|-|\.)(?:0?[13-9]|1[0-2])\2(?:29|30))

Non-Capturing Group(?:(\/|-|\.)(?:0?[13-9]|1[0-2])\2(?:29|30))

Group 2(\/|-|\.)

1st Alternative\/

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

2nd Alternative-

-the literal - (45₁₀ / 55₈ / 2D₁₆)

3rd Alternative\.

Non-Capturing Group(?:0?[13-9]|1[0-2])

\2the text saved by group 2

Non-Capturing Group(?:29|30)

$end of line

2nd Alternative ^(?:(?:(?:1[6-9]|[2-9]\d)?(?:0[48]|[2468][048]|[13579][26])|(?:(?:16|[2468][048]|[3579][26])00)))(\/|-|\.)0?2\3(?:29)$

3rd Alternative ^(?:(?:1[6-9]|[2-9]\d)?\d{2})(\/|-|\.)(?:(?:0?[1-9])|(?:1[0-2]))\4(?:0?[1-9]|1\d|2[0-8])$

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

^(?:(?:1[6-9]|[2-9]\d)?\d{2})(?:(?:(\/|-|\.)(?:0?[13578]|1[02])\1(?:31))|(?:(\/|-|\.)(?:0?[13-9]|1[0-2])\2(?:29|30)))$|
^(?:(?:(?:1[6-9]|[2-9]\d)?(?:0[48]|[2468][048]|[13579][26])|(?:(?:16|[2468][048]|[3579][26])00)))(\/|-|\.)0?2\3(?:29)$|
^(?:(?:1[6-9]|[2-9]\d)?\d{2})(\/|-|\.)(?:(?:0?[1-9])|(?:1[0-2]))\4(?:0?[1-9]|1\d|2[0-8])$

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Regular Expressions 101

Regular Expression

Extraction