Regular Expressions 101

Save & Share

  • Regex Version: ver. 3
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

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

/
/
gm

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^\w+(\s\w&\w)" test_str = ("Employee Communications & Engagement, WB\n" "SVP of Global Insights & Analytics, WB\n" "SVP of Nonfiction, HBO Max\n" "VP of Talent Relations and Development, TCM\n" "Global Franchise Management, DC\n" "WB Technology Group\n" "President, EMEA & APAC\n" "SVP & CFO, EMEA & APAC\n" "Director, Service Delivery\n" "SVP for Sales and Client Partnerships, Legacy Turner\n" "Technical Director, WarnerMedia\n" "Dir. of Brand Distribution, WarnerMedia\n" "Dir. Strategic & Consumer Insights, Turner Sports\n" "Manager for Digital Asset & Photo Library, Brand Experience\n" "Creative Manager for Creative Services, Cartoon Network\n\n\n" "// 2 words\n" "Cincinnati Bearcats\n" "Miami (FL) Hurricanes\n" "Miami (OH) Redhawks\n\n" "// three words \n" "South Florida Bulls // 2.1 \n" " Saint Joseph's Hawks\n\n" " \n" "Duke Blue Devils // 1.2\n" " UNLV Runnin' Rebels // with apostrophe\n\n" "// 4 words\n" "North Carolina Tar Heels\n" "Notre Dame Fighting Irish\n" "St John's Red Storm\n" "Florida A&M Rattlers\n" "William & Mary Tribe\n" "St Francis (PA) Red Flash\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html