Regular Expressions 101

Explanation

Pro

^start of line

Group 1([a-z][a-z0-9]{1,13}[_.\-]?[a-z0-9]{1,13})

Character Class[a-z]

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

Character Class[a-z0-9]{1,13}

{1,13}matches between 1 and 13 characters from the set below:

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

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

Character Class[_.\-]?

?matches at most one character from the set below:

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

.the literal . (46₁₀ / 56₈ / 2E₁₆)

\-the literal - (45₁₀ / 55₈ / 2D₁₆)

Character Class[a-z0-9]{1,13}

{1,13}matches between 1 and 13 characters from the set below:

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

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

@the literal @ (64₁₀ / 100₈ / 40₁₆)

Group 2((([0-9]{1,3})([.]{1})([0-9]{1,3})([.]{1})([0-9]{1,3})([.]{1})([0-9]{1,3}))|([a-z0-9]{1,10}[\-]?[a-z0-9]{1,10}[.]?[a-z0-9-]{1,10}[.]{1}[a-z]{2,4}))

1st Alternative(([0-9]{1,3})([.]{1})([0-9]{1,3})([.]{1})([0-9]{1,3})([.]{1})([0-9]{1,3}))

Group 3(([0-9]{1,3})([.]{1})([0-9]{1,3})([.]{1})([0-9]{1,3})([.]{1})([0-9]{1,3}))

Group 4([0-9]{1,3})

Character Class[0-9]{1,3}

{1,3}matches between 1 and 3 characters from the set below:

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

Group 5([.]{1})

Character Class[.]{1}

{1}matches one character from the set below:

.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 6([0-9]{1,3})

Character Class[0-9]{1,3}

{1,3}matches between 1 and 3 characters from the set below:

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

Group 7([.]{1})

Character Class[.]{1}

{1}matches one character from the set below:

.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 8([0-9]{1,3})

Character Class[0-9]{1,3}

{1,3}matches between 1 and 3 characters from the set below:

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

Group 9([.]{1})

Character Class[.]{1}

{1}matches one character from the set below:

.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 10([0-9]{1,3})

Character Class[0-9]{1,3}

{1,3}matches between 1 and 3 characters from the set below:

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

2nd Alternative([a-z0-9]{1,10}[\-]?[a-z0-9]{1,10}[.]?[a-z0-9-]{1,10}[.]{1}[a-z]{2,4})

Group 11([a-z0-9]{1,10}[\-]?[a-z0-9]{1,10}[.]?[a-z0-9-]{1,10}[.]{1}[a-z]{2,4})

Character Class[a-z0-9]{1,10}

{1,10}matches between 1 and 10 characters from the set below:

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

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

Character Class[\-]?

Character Class[a-z0-9]{1,10}

Character Class[.]?

Character Class[a-z0-9-]{1,10}

Character Class[.]{1}

Character Class[a-z]{2,4}

$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

Match Information

Detailed match information will be displayed here automatically.

Quick Reference

26 tokens

Regular Expression

^([a-z][a-z0-9]{1,13}[_.\-]?[a-z0-9]{1,13})@((([0-9]{1,3})([.]{1})([0-9]{1,3})([.]{1})([0-9]{1,3})([.]{1})([0-9]{1,3}))|([a-z0-9]{1,10}[\-]?[a-z0-9]{1,10}[.]?[a-z0-9-]{1,10}[.]{1}[a-z]{2,4}))$

//Valid
john.doe@mail.com
johndoe@mail.com
john-doe@mail.com
john_doe@mail.com
john123doe@mail.com
john123.doe@mail.com
johndoe456@mail.com
abc-d@mail.com
test@test.domain.com
test@127.1.1.1
test@test.domain.shop

// Invalid
abc-@mail.com
abc..def@mail.com
.abc@mail.com
abc#def@mail.com
123abc-d@mail.com
ABc@mail.com
test@sub.test.domain.com
test@test.domain.c

Extraction

//Valid
john.doe@mail.com
johndoe@mail.com
john-doe@mail.com
john_doe@mail.com
john123doe@mail.com
john123.doe@mail.com
johndoe456@mail.com
abc-d@mail.com
test@test.domain.com
test@127.1.1.1
test@test.domain.shop

// Invalid
abc-@mail.com
abc..def@mail.com
.abc@mail.com
abc#def@mail.com
123abc-d@mail.com
ABc@mail.com
test@sub.test.domain.com
test@test.domain.c