Regular Expressions 101

Group 1(\d)

\da digit

Positive Lookahead(?=(\d{3})+\b)

Group 2(\d{3})+

+repeats the group contents below at least once:

\d{3}a digit, repeated exactly 3 times

\ban ASCII word boundary

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

Regular Expression

(\d)(?=(\d{3})+\b)

New

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100000
1000000
10000000
100000000
1000000000
10000000000
100000000000

1
10
100
1000
10000
100000
1000000
10000000
100000000
1000000000
10000000000
100000000000