Regular Expressions 101

^start of line

Negative Lookahead(?!.*(\d)\1{6})

.*any character (except for line terminators), repeated any number of times

Group 1(\d)

\da digit

\1{6}the text saved by group 1, repeated exactly 6 times

\d{1,15}a digit, repeated between 1 and 15 times

$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{6})\d{1,15}$

New

1234567890
111111234
1231111111456
123111111456
1234567890123456