regex101: PCRE (Legacy) Substitution Workspace

Explanation

Pro

^start of line

Group 1(\*|)

1st Alternative\*

\*the literal * (42₁₀ / 52₈ / 2A₁₆)

2nd Alternative — matches an empty string

Group 2(\.|)

1st Alternative\.

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

2nd Alternative — matches an empty string

Group 3((http(s|):\/\/)|)

1st Alternative(http(s|):\/\/)

Group 4(http(s|):\/\/)

httpthe literal text http (case insensitive)

Group 5(s|)

1st Alternatives

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

2nd Alternative — matches an empty string

:the literal : (58₁₀ / 72₈ / 3A₁₆)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

2nd Alternative — matches an empty string

Group 6((?=[a-z0-9-]{1,63}\.)(xn--)?[a-z0-9]+(-[a-z0-9]+)*\.)+

+repeats the group contents below at least once:

Positive Lookahead(?=[a-z0-9-]{1,63}\.)

Character Class[a-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)

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 7(xn--)?

?repeats the group contents below at most once:

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

Character Class[a-z0-9]+

+matches at least one character from the set below:

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

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

Group 8(-[a-z0-9]+)*

*repeats the group contents below any number of times:

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Character Class[a-z0-9]+

+matches at least one character from the set below:

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

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

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 9(xn--)?

?repeats the group contents below at most once:

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

Character Class[a-z0-9-]{1,62}

{1,62}matches between 1 and 62 characters from the set below:

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

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Character Class[a-z]

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

Group 10(\/|)

1st Alternative\/

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

2nd Alternative — matches an empty string

Group 11(\*|)

1st Alternative\*

\*the literal * (42₁₀ / 52₈ / 2A₁₆)

2nd Alternative — matches an empty string

$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

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

Quick Reference

25 tokens

Regular Expression

^(\*|)(\.|)((http(s|):\/\/)|)((?=[a-z0-9-]{1,63}\.)(xn--)?[a-z0-9]+(-[a-z0-9]+)*\.)+(xn--)?[a-z0-9-]{1,62}[a-z](\/|)(\*|)$

New

###      REGEX FOR DOMAIN NAME VALIDATION      ###
### From PHPfrance : https://www.phpfrance.com ###



### List of example valid domain names ###

www.google.com
google.com
google.xn--pgbs0dh
google.co.uk
mkyong123.com
mkyong-info.com
sub.mkyong.com
sub.mkyong-info.com
mkyong.com.au
g.co
mkyong.t.t.co
xn--c6h.com
www.domain.photography
http://www.google.com
https://www.google.com



### List of invalid domain names examples, and why ###

# Tld must not be less than 2 characters
mkyong.t.t.c

# Comma is not allow
mkyong,com

# No Tld
mkyong

# Tld not allow ONLY digits
mkyong.123

# Must start with [a-z0-9]
.com

# No Tld
mkyong.com/users

# Cannot begin with a hyphen -
-mkyong.com

# Cannot end with a hyphen -
mkyong-.com

# Cannot begin with a hyphen -
sub.-mkyong.com



### Test all 1531 existing TLDs (as of 2019-05-29)
### Source : http://data.iana.org/TLD/tlds-alpha-by-domain.txt

test.aaa
test.aarp
test.abarth
test.abb
test.abbott
test.abbvie
test.abc
test.able
test.abogado
test

Substitution

*.$6/*

###      REGEX FOR DOMAIN NAME VALIDATION      ###
### From PHPfrance : https://www.phpfrance.com ###



### List of example valid domain names ###

www.google.com
google.com
google.xn--pgbs0dh
google.co.uk
mkyong123.com
mkyong-info.com
sub.mkyong.com
sub.mkyong-info.com
mkyong.com.au
g.co
mkyong.t.t.co
xn--c6h.com
www.domain.photography
http://www.google.com
https://www.google.com



### List of invalid domain names examples, and why ###

# Tld must not be less than 2 characters
mkyong.t.t.c

# Comma is not allow
mkyong,com

# No Tld
mkyong

# Tld not allow ONLY digits
mkyong.123

# Must start with [a-z0-9]
.com

# No Tld
mkyong.com/users

# Cannot begin with a hyphen -
-mkyong.com

# Cannot end with a hyphen -
mkyong-.com

# Cannot begin with a hyphen -
sub.-mkyong.com



### Test all 1531 existing TLDs (as of 2019-05-29)
### Source : http://data.iana.org/TLD/tlds-alpha-by-domain.txt

test.aaa
test.aarp
test.abarth
test.abb
test.abbott
test.abbvie
test.abc
test.able
test.abogado
test