Regular Expressions 101

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  • Unit Tests (21)

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

$re = '/^((((\d+,)+\d+|(\d+(\/|-|#)\d+)|\d+L?|\*(\/\d+)?|L(-\d+)?|\?|[A-Z]{3}(-[A-Z]{3})?) ?){5,7})|(@(annually|yearly|monthly|weekly|daily|hourly|reboot))|(@every (\d+(ns|us|µs|ms|s|m|h))+)$/m'; $str = '# cron 0 0 1 1 * 1 0 0 1 1 * 1,2 0 0 1 1 * 1,2,3 0 0 1 * * 1/4 0 0 * * 0 1-4 0 0 * * * 2/4 0 * * * * * # variations 10 12 * * 1,2,3,4,5 * 10 12 * * 1,2,3,4,5 * */5 * * * * */4 */4 */4 * * * # At 12:00 pm (noon) every day during the year 2017: 0 0 12 * * ? 2017 # Every 5 minutes starting at 1 pm and ending on 1:55 pm and then starting at 6 pm and ending at 6:55 pm, every day: 0 0/5 13,18 * * ? # Every minute starting at 1 pm and ending on 1:05 pm, every day: 0 0-5 13 * * ? # At 1:15 pm and 1:45 pm every Tuesday in the month of June: 0 15,45 13 ? 6 Tue # At 9:30 am every Monday, Tuesday, Wednesday, Thursday, and Friday: 0 30 9 ? * MON-FRI # At 9:30 am on 15th day of every month: 0 30 9 15 * ? # At 6 pm on the last day of every month: 0 0 18 L * ? # At 6 pm on the 3rd to last day of every month: 0 0 18 L-3 * ? # At 10:30 am on the last Thursday of every month: 0 30 10 ? * 5L # At 6 pm on the last Friday of every month during the years 2015, 2016 and 2017: 0 0 18 ? * 6L 2015-2017 # At 10 am on the third Monday of every month: 0 0 10 ? * 2#3 # At 12 am midnight on every day for five days starting on the 10th day of the month: 0 0 0 10/5 * ? # more 0 0 12 * * ? 0 15 10 ? * * 0 15 10 * * ? 0 15 10 * * ? * 0 15 10 * * ? 2005 0 * 14 * * ? 0 0/5 14 * * ? 0 0/5 14,18 * * ? 0 0-5 14 * * ? 0 10,44 14 ? 3 WED 0 15 10 ? * MON-FRI 0 15 10 15 * ? 0 15 10 ? * 6L 0 15 10 ? * 6L 2002-2005 0 15 10 ? * 6#3 0 0 12 1/5 * ? 0 11 11 11 11 ? # predefined @annually @yearly @monthly @weekly @daily @hourly @reboot # every @every 5s @every 20h30m #individual forms 1,2,3 1,2 1/2 1-2 1 * 0 */4 6#3 L 5L L-2 '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php