Regular Expressions 101

Pro

^start of line

Group 1([a-zA-Z0-9-_]{0,63}\.?[a-zA-Z0-9-_]{1,63}\.[a-zA-Z0-9-_]{1,63})

Character Class[a-zA-Z0-9-_]{0,63}

{0,63}matches between 0 and 63 characters from the set below:

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

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

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

\.?optionally matches the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[a-zA-Z0-9-_]{1,63}

{1,63}matches between 1 and 63 characters from the set below:

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

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

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[a-zA-Z0-9-_]{1,63}

{1,63}matches between 1 and 63 characters from the set below:

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

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

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

:?optionally matches the literal : (58₁₀ / 72₈ / 3A₁₆)

Group 2(\d{1,5})?

?repeats the group contents below at most once:

\d{1,5}a Unicode decimal digit, repeated between 1 and 5 times

$end of line

Global pattern flags

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

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

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

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

^([a-zA-Z0-9-_]{0,63}\.?[a-zA-Z0-9-_]{1,63}\.[a-zA-Z0-9-_]{1,63}):?(\d{1,5})?$

New

.com
a.com
aa.com
a.a.com
a.a.a.com

Domain-123.com
subDomain.Domain-123.com
test.subDomain.Domain-123.com

Domain-123.com:12345
subDomain.Domain-123.com:12345
test.subDomain.Domain-123.com:12345