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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

const regex = /^(?:(?:\+|00)33[\s.-]{0,3}(?:\(0\)[\s.-]{0,3})?|0)[1-9](?:(?:[\s.-]?\d{2}){4}|\d{2}(?:[\s.-]?\d{3}){2})$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?:(?:\\+|00)33[\\s.-]{0,3}(?:\\(0\\)[\\s.-]{0,3})?|0)[1-9](?:(?:[\\s.-]?\\d{2}){4}|\\d{2}(?:[\\s.-]?\\d{3}){2})$', 'gm') const str = `French Phone Number Validation. Accept several kind of format, more or less usual. And refuse incorrect formats. - Prefix: 0033 / +33 / (0) / 0 - Number: collapsed / group by 2 / group by 3 - Separator: space / dot / dash ~ Accepted ~ 0123456789 01 23 45 67 89 01.23.45.67.89 0123 45.67.89 0033 123-456-789 0033(0)123456789 +33-1.23.45.67.89 +33 - 123 456 789 +33(0) 123 456 789 +33 (0)123 45 67 89 +33 (0)1 2345-6789 +33(0) - 123456789 ~ Rejected ~ 012345678 01234567890 0+123456789 (0)123456789 01 23 45 67 89 ~ Accepted but strange ~ +33.-.123456789 +33.-.(0)-.-123456789 01 23.45-67.89 `; const subst = `false`; // The substituted value will be contained in the result variable const result = str.replace(regex, subst); console.log('Substitution result: ', result);

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions