Regular Expressions 101

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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

/
/
g

Test String

Code Generator

Language

Generated Code

$re = '/#{(\w+[.\w+]+)\}/'; $str = 'The [#{product.name}](/card-details/card-name/#{details.slug.value}) which has an annual fee of #{details.annual_fee.value}, does double-duty as a rewards credit card and a balance transfer credit card. You’ll get a big sign-up bonus: Discover will automatically double cash back for new card holders in your first year. Plus, when you opt in to a bonus rewards program, this card earns 5% cash back on rotating bonus categories like gas and restaurants. Be aware that these 5% rewards are capped at $1,500 spent per quarter. On all other purchases, you’ll get 1% cash back. There is #{details.pros_bullets.value.1} and it comes with a generous 0% APR offer: #{details.apr_intro_message_list.value.0}. The card charges a 3% balance transfer fee, and Discover isn’t widely accepted abroad. But it could be a great choice if you’re trying to earn big rewards on new purchases while paying off an old debt.'; preg_match_all($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