regex101: Valid date (DD-MM-YYYY) from 1900 to 2099

^start of line

Group 1((0)*[1-9]|1[012]|3[01])

1st Alternative(0)*[1-9]

Group 2(0)*

*repeats the group contents below any number of times:

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[1-9]

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

2nd Alternative1[012]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[012]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

3rd Alternative3[01]

3the literal 3 (51₁₀ / 63₈ / 33₁₆)

Character Class[01]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 3((0)*[1-9]|1[012]|2[012]|3[01])

1st Alternative(0)*[1-9]

Group 4(0)*

*repeats the group contents below any number of times:

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[1-9]

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

2nd Alternative1[012]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[012]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

3rd Alternative2[012]

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[012]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

4th Alternative3[01]

3the literal 3 (51₁₀ / 63₈ / 33₁₆)

Character Class[01]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 5(19[0-9][0-9]|20[0-9][0-9])

1st Alternative19[0-9][0-9]

19the literal text 19

Character Class[0-9]

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

Character Class[0-9]

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

2nd Alternative20[0-9][0-9]

20the literal text 20

Character Class[0-9]

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

Character Class[0-9]

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

$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

Search reference

Regular Expression

^((0)*[1-9]|1[012]|3[01])-((0)*[1-9]|1[012]|2[012]|3[01])-(19[0-9][0-9]|20[0-9][0-9])$

Test String
New

02-19-2020
12-3-2020
3-12-2020
3-4-1222
31-07-2321
7-7-2083

Regular Expression

Test StringNew

Test String
New