Regular Expressions 101

^start of line

\d{1,4}a digit, repeated between 1 and 4 times

Character Class[A-Z\d]?

?matches at most one character from the set below:

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

\da digit

$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

^\d{1,4}[A-Z\d]?$

New

1A
11A
111A
1111A
1
11
111
1111
11111

1A11
2A2
222A1
A11
AA
AA1
A1A