Regular Expressions 101

Non-Capturing Group(?:(?!\b-\b|-\b)(?:.|^))

Negative Lookahead(?!\b-\b|-\b)

1st Alternative\b-\b

\ban ASCII word boundary

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\ban ASCII word boundary

2nd Alternative-\b

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\ban ASCII word boundary

Non-Capturing Group(?:.|^)

1st Alternative.

.any character (except for line terminators)

2nd Alternative^

^start of line

\ban ASCII word boundary

Group 1(\d{4})

\d{4}a digit, repeated exactly 4 times

\ban ASCII word boundary

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

(?:(?!\b-\b|-\b)(?:.|^))\b(\d{4})\b

New

2014
1106 **2014** **9899** 
**11500**

234-233-2014
234-234-1100
-1100