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

/
/
gmx

Test String

Code Generator

Language

Generated Code

$re = '/\b \+?1? (?<separator>\s|-|\.)? (?: # area code with optional parentheses (?<area_code>[2-9][0-8]\d) |\((?&area_code)\) ) (?&separator)? (?: # exchange (?!555) [2-9] (?!11)\d\d ) (?&separator)? \d{4} # line \b/mx'; $str = '212 718-1234 (212)718-1234 (212) 718-1234 1(212)718-1234 1-212-718-1234 1.212.718.1234 +1-212-718-1234 +1.212.718.1234 1-212-718-1234 +1 (212) 718-1234 # 1-VALID 2-VALID 4-VALID 231 212 1234 234-235-5678 is a valid telephone number with area code 234, central office prefix (exchange) 235, and line number 5678. 12127181234 (212)7181234 # 1-INVALID 2-INVALID 4-INVALID 091 012 1234 # 1-INVALID 2-VALID 4-INVALID 081 012 1234 171 012 1234 # 1-VALID 2-VALID 4-INVALID 231 012 1234 # 1-INVALID 2-INVALID 4-VALID 091 212 1234 # 1-INVALID 2-VALID 4-VALID 081 212 1234 171 212 1234 231 555 1234 867-5309 missing area code The number 234-911-5678 is invalid, because the central office code must not be in the form N11. 314-159-2653 is invalid, because the office code must not begin with 1. 123-234-5678 is invalid, because the NPA must not begin with 0 or 1. 1 212) 718 1234 121271812341212718123412127181234'; preg_match_all($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