Regular Expressions 101

^start of line

Non-Capturing Group(?:\[(?:\\.|[^\]])*\]|\(\?:|[^(\\]|\\\D|\(\?[gmixsu])*

*repeats the group contents below any number of times:

1st Alternative\[(?:\\.|[^\]])*\]

\[the literal [ (91₁₀ / 133₈ / 5B₁₆)

Non-Capturing Group(?:\\.|[^\]])*

*repeats the group contents below any number of times:

1st Alternative\\.

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

.any Unicode character (except for line terminators)

2nd Alternative[^\]]

Negated Character Class[^\]]

\]the literal ] (93₁₀ / 135₈ / 5D₁₆)

2nd Alternative\(\?:

\(the literal ( (40₁₀ / 50₈ / 28₁₆)

\?the literal ? (63₁₀ / 77₈ / 3F₁₆)

:the literal : (58₁₀ / 72₈ / 3A₁₆)

3rd Alternative[^(\\]

Negated Character Class[^(\\]

(the literal ( (40₁₀ / 50₈ / 28₁₆)

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

4th Alternative\\\D

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

\Dany character that is not a Unicode decimal digit

5th Alternative\(\?[gmixsu]

\(the literal ( (40₁₀ / 50₈ / 28₁₆)

\?the literal ? (63₁₀ / 77₈ / 3F₁₆)

Character Class[gmixsu]

gthe literal g (103₁₀ / 147₈ / 67₁₆) (case sensitive)

mthe literal m (109₁₀ / 155₈ / 6D₁₆) (case sensitive)

ithe literal i (105₁₀ / 151₈ / 69₁₆) (case sensitive)

xthe literal x (120₁₀ / 170₈ / 78₁₆) (case sensitive)

sthe literal s (115₁₀ / 163₈ / 73₁₆) (case sensitive)

uthe literal u (117₁₀ / 165₈ / 75₁₆) (case sensitive)

$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

^(?:\[(?:\\.|[^\]])*\]|\(\?:|[^(\\]|\\\D|\(\?[gmixsu])*$

New

(?i)
abc.*
(\d)
(?:foo)?
[()]
\2
(?P<group>text)
\(foo)