Regular Expressions 101

Pro

Negative Lookbehind(?<!\S)

\Sany character that is not Unicode whitespace

Character Class[a-zA-Z\d]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

\da Unicode decimal digit

Non-Capturing Group(?:[.-][a-zA-Z\d]+)?

?repeats the group contents below at most once:

Character Class[.-]

.the literal . (46₁₀ / 56₈ / 2E₁₆)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Character Class[a-zA-Z\d]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

\da Unicode decimal digit

Negative Lookahead(?!\S)

\Sany character that is not Unicode whitespace

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

(?<!\S)[a-zA-Z\d]+(?:[.-][a-zA-Z\d]+)?(?!\S)

New

ab.ab
ab.ab.ab
ab.
.ab
.Ab
Ab.
Ab.A
ab
a
sample text ..teste...tetes ab. .ab test

ab.ab
ab.ab.ab
ab.
.ab
.Ab
Ab.
Ab.A
ab
a
sample text ..teste...tetes ab. .ab test