Regular Expressions 101

^start of line

Negative Lookahead(?!\d+$)

\d+a digit, repeated at least once

$end of line

Non-Capturing Group(?:[a-zA-Z0-9][a-zA-Z0-9 @&$]*)?

?repeats the group contents below at most once:

Character Class[a-zA-Z0-9]

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

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

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

Character Class[a-zA-Z0-9 @&$]*

*matches any number of characters from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

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

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

the literal (32₁₀ / 40₈ / 20₁₆)

@the literal @ (64₁₀ / 100₈ / 40₁₆)

&the literal & (38₁₀ / 46₈ / 26₁₆)

$the literal $ (36₁₀ / 44₈ / 24₁₆)

$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+$)(?:[a-zA-Z0-9][a-zA-Z0-9 @&$]*)?$

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