Regular Expressions 101

^start of string

Group 1((?!(.*[a-z ].*[a-z ].*))([0-9a-z ]{12})|(?!(.*[a-z ].*[a-z ].*))([0-9a-z ]{14}))

1st Alternative(?!(.*[a-z ].*[a-z ].*))([0-9a-z ]{12})

Negative Lookahead(?!(.*[a-z ].*[a-z ].*))

Group 2(.*[a-z ].*[a-z ].*)

.*any character (except for line terminators), repeated any number of times

Character Class[a-z ]

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

the literal (32₁₀ / 40₈ / 20₁₆)

.*any character (except for line terminators), repeated any number of times

Character Class[a-z ]

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

the literal (32₁₀ / 40₈ / 20₁₆)

.*any character (except for line terminators), repeated any number of times

Group 3([0-9a-z ]{12})

Character Class[0-9a-z ]{12}

{12}matches exactly 12 characters from the set below:

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

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

the literal (32₁₀ / 40₈ / 20₁₆)

2nd Alternative(?!(.*[a-z ].*[a-z ].*))([0-9a-z ]{14})

Negative Lookahead(?!(.*[a-z ].*[a-z ].*))

Group 4(.*[a-z ].*[a-z ].*)

.*any character (except for line terminators), repeated any number of times

Character Class[a-z ]

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

the literal (32₁₀ / 40₈ / 20₁₆)

.*any character (except for line terminators), repeated any number of times

Character Class[a-z ]

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

the literal (32₁₀ / 40₈ / 20₁₆)

.*any character (except for line terminators), repeated any number of times

Group 5([0-9a-z ]{14})

Character Class[0-9a-z ]{14}

{14}matches exactly 14 characters from the set below:

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

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

the literal (32₁₀ / 40₈ / 20₁₆)

$end of string

Global pattern flags

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

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

^((?!(.*[a-z ].*[a-z ].*))([0-9a-z ]{12})|(?!(.*[a-z ].*[a-z ].*))([0-9a-z ]{14}))$

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