Regular Expressions 101

^start of line

Character Class[A-Za-z0-9]{15}

{15}matches exactly 15 characters from the set below:

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

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

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

Non-Capturing Group(?:[A-Za-z0-9]{3})?

?repeats the group contents below at most once:

Character Class[A-Za-z0-9]{3}

{3}matches exactly 3 characters from the set below:

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

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

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

$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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

^[A-Za-z0-9]{15}(?:[A-Za-z0-9]{3})?$

New

001i000001AWbWuGTA
001i000001AWbWugta
50130000000014c
50130000000014C
50130000000014ca
50130000000014cab
50130000000014cabde