Regular Expressions 101

Pro

\[?optionally matches the literal [ (91₁₀ / 133₈ / 5B₁₆)

\ba Unicode word boundary

Group 1((?:[01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9](?:\.[0-9]+)?)

Non-Capturing Group(?:[01][0-9]|2[0-3])

1st Alternative[01][0-9]

Character Class[01]

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)

2nd Alternative2[0-3]

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[0-3]

0-3one character from 0 (48₁₀) to 3 (51₁₀)

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Character Class[0-5]

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

Character Class[0-9]

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

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Character Class[0-5]

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

Character Class[0-9]

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

Non-Capturing Group(?:\.[0-9]+)?

?repeats the group contents below at most once:

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[0-9]+

+matches at least one character from the set below:

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

\ba Unicode word boundary

]?optionally matches the literal ] (93₁₀ / 135₈ / 5D₁₆)

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.

25 tokens

\[?\b((?:[01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9](?:\.[0-9]+)?)\b]?

[12:45:34] or [02:05:23.56]
12:45:34 or 02:05:23.56
[12:45:34 or 02:05:23.56]

[12:45:34] or [02:05:23.56]
12:45:34 or 02:05:23.56
[12:45:34 or 02:05:23.56]