regex101: PCRE (Legacy) Match Workspace

Pro

\ban ASCII word boundary

Non-Capturing Group(?:(?:0[1-9]|1\d|2[0-8]|[1-9])-(?:0?2)-(?:\d+)|(?:0[1-9]|1\d|2\d|[1-9])-(?:0?2)-(?:(?:\d*?(?:(?:0[48]|[13579][26]|[2468][048])|(?:(?:[02468][048]|[13579][26])00))|[48]00|[48])(?=\D|\b))|(?:0[1-9]|1\d|2\d|30|[1-9])-(?:0?[469]|11)-(?:\d+)|(?:0[1-9]|1\d|2\d|3[01]|[1-9])-(?:0?[13578]|1[02])-(?:\d+))

1st Alternative(?:0[1-9]|1\d|2[0-8]|[1-9])-(?:0?2)-(?:\d+)

Non-Capturing Group(?:0[1-9]|1\d|2[0-8]|[1-9])

1st Alternative0[1-9]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

2nd Alternative1\d

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

\da digit

3rd Alternative2[0-8]

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[0-8]

0-8one character from 0 (48₁₀) to 8 (56₁₀)

4th Alternative[1-9]

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Non-Capturing Group(?:0?2)

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

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Non-Capturing Group(?:\d+)

\d+a digit, repeated at least once

2nd Alternative(?:0[1-9]|1\d|2\d|[1-9])-(?:0?2)-(?:(?:\d*?(?:(?:0[48]|[13579][26]|[2468][048])|(?:(?:[02468][048]|[13579][26])00))|[48]00|[48])(?=\D|\b))

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

1st Alternative0[1-9]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

2nd Alternative1\d

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

\da digit

3rd Alternative2\d

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

\da digit

4th Alternative[1-9]

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Non-Capturing Group(?:0?2)

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

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Non-Capturing Group(?:(?:\d*?(?:(?:0[48]|[13579][26]|[2468][048])|(?:(?:[02468][048]|[13579][26])00))|[48]00|[48])(?=\D|\b))

Non-Capturing Group(?:\d*?(?:(?:0[48]|[13579][26]|[2468][048])|(?:(?:[02468][048]|[13579][26])00))|[48]00|[48])

1st Alternative\d*?(?:(?:0[48]|[13579][26]|[2468][048])|(?:(?:[02468][048]|[13579][26])00))

\d*?a digit, repeated any number of times

Non-Capturing Group(?:(?:0[48]|[13579][26]|[2468][048])|(?:(?:[02468][048]|[13579][26])00))

1st Alternative(?:0[48]|[13579][26]|[2468][048])

2nd Alternative(?:(?:[02468][048]|[13579][26])00)

2nd Alternative[48]00

3rd Alternative[48]

Positive Lookahead(?=\D|\b)

3rd Alternative(?:0[1-9]|1\d|2\d|30|[1-9])-(?:0?[469]|11)-(?:\d+)

4th Alternative(?:0[1-9]|1\d|2\d|3[01]|[1-9])-(?:0?[13578]|1[02])-(?:\d+)

\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

25 tokens

Regular Expression

\b(?:(?:0[1-9]|1\d|2[0-8]|[1-9])-(?:0?2)-(?:\d+)|(?:0[1-9]|1\d|2\d|[1-9])-(?:0?2)-(?:(?:\d*?(?:(?:0[48]|[13579][26]|[2468][048])|(?:(?:[02468][048]|[13579][26])00))|[48]00|[48])(?=\D|\b))|(?:0[1-9]|1\d|2\d|30|[1-9])-(?:0?[469]|11)-(?:\d+)|(?:0[1-9]|1\d|2\d|3[01]|[1-9])-(?:0?[13578]|1[02])-(?:\d+))\b

New

29-02-2016 - valid
29-02-2017 - invalid (not leap year)
30-03-2016 - valid
29-2-2017  - invalid (not leap year)
28-2-2017  - valid
2-2-2017   - valid
31-11-2017 - invalid (November has 30 days)
30-11-2017 - valid

Extraction

29-02-2016 - valid
29-02-2017 - invalid (not leap year)
30-03-2016 - valid
29-2-2017  - invalid (not leap year)
28-2-2017  - valid
2-2-2017   - valid
31-11-2017 - invalid (November has 30 days)
30-11-2017 - valid