Regular Expressions 101

^start of line

Group 1([0-9]{4}|[0-9]{6})

1st Alternative[0-9]{4}

Character Class[0-9]{4}

{4}matches exactly 4 characters from the set below:

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

2nd Alternative[0-9]{6}

Character Class[0-9]{6}

{6}matches exactly 6 characters from the set below:

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

^([0-9]{4}|[0-9]{6})$

New

stringtest3abc
or 2 here
1234
123456