regex101: PCRE (Legacy) Match Workspace

Pro

^start of line

Negative Lookahead(?!-)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 1(xn--)?

?repeats the group contents below at most once:

xn--the literal text xn-- (case sensitive)

Character Class[a-zA-Z0-9]

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

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

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

Character Class[a-zA-Z0-9-_]{0,61}

{0,61}matches between 0 and 61 characters 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)

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

Character Class[a-zA-Z0-9]{0,1}

{0,1}matches at most 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)

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

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Negative Lookahead(?!-)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 2(xn--)?

?repeats the group contents below at most once:

xn--the literal text xn-- (case sensitive)

Group 3([a-zA-Z0-9\-]{1,50}|[a-zA-Z0-9-]{1,30}\.[a-zA-Z]{2,})

1st Alternative[a-zA-Z0-9\-]{1,50}

Character Class[a-zA-Z0-9\-]{1,50}

{1,50}matches between 1 and 50 characters 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)

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

\-the literal - (45₁₀ / 55₈ / 2D₁₆)

2nd Alternative[a-zA-Z0-9-]{1,30}\.[a-zA-Z]{2,}

Character Class[a-zA-Z0-9-]{1,30}

{1,30}matches between 1 and 30 characters 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)

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[a-zA-Z]{2,}

{2,}matches at least 2 characters 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)

$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

25 tokens

Regular Expression

^(?!-)(xn--)?[a-zA-Z0-9][a-zA-Z0-9-_]{0,61}[a-zA-Z0-9]{0,1}\.(?!-)(xn--)?([a-zA-Z0-9\-]{1,50}|[a-zA-Z0-9-]{1,30}\.[a-zA-Z]{2,})$

New

#Valid
xn-fsqu00a.xn-0zwm56d
xn-fsqu00a.xn--vermgensberatung-pwb
xn--stackoverflow.com
stackoverflow.xn--com
stackoverflow.co.uk
google.com.au
i.oh1.me
wow.british-library.uk
xn--stackoverflow.com
stackoverflow.xn--com
stackoverflow.co.uk
0-0O_.COM
a.net
0-0O.COM
0-OZ.CO.uk
0-TENSION.COM.br
0-WH-AO14-0.COM-com.net
a-1234567890-1234567890-1234567890-1234567890-1234567890-1234-z.eu.us
#Invalid
-0-0O.COM
0-0O.-COM
-a.dot
a-1234567890-1234567890-1234567890-1234567890-1234567890-12345-z.eu.us

Extraction

#Valid
xn-fsqu00a.xn-0zwm56d
xn-fsqu00a.xn--vermgensberatung-pwb
xn--stackoverflow.com
stackoverflow.xn--com
stackoverflow.co.uk
google.com.au
i.oh1.me
wow.british-library.uk
xn--stackoverflow.com
stackoverflow.xn--com
stackoverflow.co.uk
0-0O_.COM
a.net
0-0O.COM
0-OZ.CO.uk
0-TENSION.COM.br
0-WH-AO14-0.COM-com.net
a-1234567890-1234567890-1234567890-1234567890-1234567890-1234-z.eu.us
#Invalid
-0-0O.COM
0-0O.-COM
-a.dot
a-1234567890-1234567890-1234567890-1234567890-1234567890-12345-z.eu.us