Regular Expressions 101

Pro

Negative Lookbehind(?<![A-Z0-9])

Character Class[A-Z0-9]

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

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

Positive Lookahead(?=[A-Z0-9]{10}(?:[^A-Z0-9]|$))

Character Class[A-Z0-9]{10}

{10}matches exactly 10 characters from the set below:

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

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

Non-Capturing Group(?:[^A-Z0-9]|$)

1st Alternative[^A-Z0-9]

Negated Character Class[^A-Z0-9]

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

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

2nd Alternative$

$end of line

Group 1([^0]*0*(?=(?:[^A-Z0-9]|$)))

Negated Character Class[^0]*

*matches any number of characters outside the set below:

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

0*the literal 0 (48₁₀ / 60₈ / 30₁₆) , repeated any number of times

Positive Lookahead(?=(?:[^A-Z0-9]|$))

Non-Capturing Group(?:[^A-Z0-9]|$)

1st Alternative[^A-Z0-9]

Negated Character Class[^A-Z0-9]

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

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

2nd Alternative$

$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.

25 tokens

(?<![A-Z0-9])(?=[A-Z0-9]{10}(?:[^A-Z0-9]|$))([^0]*0*(?=(?:[^A-Z0-9]|$)))

New

ABC1000000 - valid
3212130000 - valid
0000000000 - valid
ABC1000100 - invalid
0001000000 - invalid
0000
0 0000000000
00000000000

ABC1000000 - valid
3212130000 - valid
0000000000 - valid
ABC1000100 - invalid
0001000000 - invalid
0000
0 0000000000
00000000000