Regular Expressions 101

Pro

Group 1(AB(?:[0-9A-Z]{5}|[0-9]{4}))

ABthe literal text AB (case sensitive)

Non-Capturing Group(?:[0-9A-Z]{5}|[0-9]{4})

1st Alternative[0-9A-Z]{5}

Character Class[0-9A-Z]{5}

{5}matches exactly 5 characters from the set below:

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

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

2nd 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)

Non-Capturing Group(?:\s+)

\s+any whitespace character, repeated at least once

Global pattern flags

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

Detailed match information will be displayed here automatically.

25 tokens

(AB(?:[0-9A-Z]{5}|[0-9]{4}))(?:\s+)

New

foo
AB0001
AB0002 foo
foo AB0003
foo AB0004A AB0004.1
AB0005.1 foo AB0005A bar AB0005