Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

re = /^(?:(?:\+|00)33[\s.-]{0,3}(?:\(0\)[\s.-]{0,3})?|0)[1-9](?:(?:[\s.-]?\d{2}){4}|\d{2}(?:[\s.-]?\d{3}){2})$/m 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 ' subst = 'false' result = str.gsub(re, subst) # Print the result of the substitution puts 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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html