Regular Expressions 101

Non-Capturing Group(?:([0-2]?[1-9]):([0-5][0-9])(?: ?([ap]m?))?|([0-2]?[1-9])(?: ?([ap]m?)))

1st Alternative([0-2]?[1-9]):([0-5][0-9])(?: ?([ap]m?))?

Group 1([0-2]?[1-9])

Character Class[0-2]?

?matches at most one character from the set below:

0-2one character from 0 (48₁₀) to 2 (50₁₀)

Character Class[1-9]

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

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Group 2([0-5][0-9])

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(?: ?([ap]m?))?

?repeats the group contents below at most once:

?optionally matches the literal (32₁₀ / 40₈ / 20₁₆)

Group 3([ap]m?)

Character Class[ap]

athe literal a (97₁₀ / 141₈ / 61₁₆) (case insensitive)

pthe literal p (112₁₀ / 160₈ / 70₁₆) (case insensitive)

m?optionally matches the literal m (109₁₀ / 155₈ / 6D₁₆) (case insensitive)

2nd Alternative([0-2]?[1-9])(?: ?([ap]m?))

Group 4([0-2]?[1-9])

Character Class[0-2]?

?matches at most one character from the set below:

0-2one character from 0 (48₁₀) to 2 (50₁₀)

Character Class[1-9]

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

Non-Capturing Group(?: ?([ap]m?))

?optionally matches the literal (32₁₀ / 40₈ / 20₁₆)

Group 5([ap]m?)

Character Class[ap]

athe literal a (97₁₀ / 141₈ / 61₁₆) (case insensitive)

pthe literal p (112₁₀ / 160₈ / 70₁₆) (case insensitive)

m?optionally matches the literal m (109₁₀ / 155₈ / 6D₁₆) (case insensitive)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

i modifier: insensitive. Matches without distinguishing uppercase and lowercase letters

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

(?:([0-2]?[1-9]):([0-5][0-9])(?: ?([ap]m?))?|([0-2]?[1-9])(?: ?([ap]m?)))

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