Regular Expressions 101

1st Alternative(([0-9]{4})-([0-9]{2})-([0-9]{2}))

Group 1(([0-9]{4})-([0-9]{2})-([0-9]{2}))

Group 2([0-9]{4})

Character Class[0-9]{4}

{4}matches exactly 4 characters from the set below:

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 3([0-9]{2})

Character Class[0-9]{2}

{2}matches exactly 2 characters from the set below:

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 4([0-9]{2})

Character Class[0-9]{2}

{2}matches exactly 2 characters from the set below:

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

2nd Alternative(([0-9]{4})\/([0-9]{2})\/([0-9]{2}))

Group 5(([0-9]{4})\/([0-9]{2})\/([0-9]{2}))

Group 6([0-9]{4})

Character Class[0-9]{4}

{4}matches exactly 4 characters from the set below:

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

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

Group 7([0-9]{2})

Character Class[0-9]{2}

{2}matches exactly 2 characters from the set below:

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

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

Group 8([0-9]{2})

Character Class[0-9]{2}

{2}matches exactly 2 characters from the set below:

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

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

(([0-9]{4})-([0-9]{2})-([0-9]{2}))|(([0-9]{4})\/([0-9]{2})\/([0-9]{2}))

New

2019/12/13
2019-12-13