Regular Expressions 101

^start of line

Group 1([1-9]\d*)

Character Class[1-9]

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

\d*a digit, repeated any number of times

-the literal - (45₁₀ / 55₈ / 2D₁₆)

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

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[0-2]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[0-2]

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 3(0?[1-9]|[1-2]\d|3[0-2])

1st Alternative0?[1-9]

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

Character Class[1-9]

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

2nd Alternative[1-2]\d

Character Class[1-2]

1-2one character from 1 (49₁₀) to 2 (50₁₀)

\da digit

3rd Alternative3[0-2]

3the literal 3 (51₁₀ / 63₈ / 33₁₆)

Character Class[0-2]

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

Non-Capturing Group(?:\x20([01][0-9]|2[0-3]):([0-5]\d):([0-5]\d)(\.\d+)?)?

?repeats the group contents below at most once:

\x20the literal (20₁₆ / 40₈ / 32₁₀)

Group 4([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)

Group 5([0-5]\d)

Character Class[0-5]

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

\da digit

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Group 6([0-5]\d)

Character Class[0-5]

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

\da digit

Group 7(\.\d+)?

$end of line

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.

Search reference

Regular Expression

^([1-9]\d*)-(0[1-9]|1[0-2])-(0?[1-9]|[1-2]\d|3[0-2])(?:\x20([01][0-9]|2[0-3]):([0-5]\d):([0-5]\d)(\.\d+)?)?$

New

2015-03-32 07:00:00
2015-05-15 12:00:54.02911

Regular Expression

Extraction