Regular Expressions 101

1st Alternative(2[1-9]|[3-9]\d|1\d\d)

Group 1(2[1-9]|[3-9]\d|1\d\d)

1st Alternative2[1-9]

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

2nd Alternative[3-9]\d

Character Class[3-9]

3-9one character from 3 (51₁₀) to 9 (57₁₀)

\da digit

3rd Alternative1\d\d

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

\da digit

2nd Alternative([0-9]|1[0-9]|20)

Group 2([0-9]|1[0-9]|20)

1st Alternative[0-9]

Character Class[0-9]

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

2nd Alternative1[0-9]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[0-9]

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

3rd Alternative20

20the literal text 20

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

(2[1-9]|[3-9]\d|1\d\d)|([0-9]|1[0-9]|20)

New

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