Regular Expressions 101

Save & Share

  • Regex Version: ver. 249
  • 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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

"
"

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = ",(?=(?:[^\\\"]*\\\"[^\\\"]*\\\")*[^\\\"]*$)"; final String string = "Column,Row,Value,Column Title,Question,Answer\n" + "A,1,100,Comics,\"This series following a team of mutants, was actually cancelled during it's first run and did not reach its popular status until a revival severla years later.\",X-Men\n" + "A,2,200,Comics,This demonic hero has a big gun and an even bigger right fist.,Hellboy\n" + "A,3,300,Comics,This mostly self-published series follows three osteo-minded cousins through a series of misadventures.,Who is...\n" + "A,4,400,Comics,\"Superman may be considered the first, but this magical superhero also debuted in Action Comics #1, 7 pages after Superman.\",Zatara\n" + "A,5,500,Comics,\"Sharing the alias of a few villainous iterations in the main comics, this character from the \"\"What If?\"\" line of comics is a spider bitten by a radioactive human.\",Webster Weaver / Man-Spider\n" + "B,1,100,Disney,\"One of these per day will keep the doctor away, but a poisoned one requires a visit from nobility.\",An Apple\n" + "B,2,200,Disney,\"This character, one of seven of his kind, is the only one who's name is not an adjective.\",Doc\n" + "B,3,300,Disney,This kitchen essential is the weapon of choice for Rapunzel.,A cast iron frying pan\n" + "B,4,400,Disney,Billy Joel lends his voice to this canine character.,Dodger\n" + "B,5,500,Disney,This is the last animated feature to be produced by Walt Disney until his death in 1966.,The Jungle Book\n" + "C,1,100,MTG,\"A player of the game is called this, eventually added as a card type.\",A Planeswalker\n" + "C,2,200,MTG,Much of early Magic is set on this plane.,Dominaria\n" + "C,3,300,MTG,This space between planes is also the original home of the Eldrazi.,The Blind Eternities\n" + "C,4,400,MTG,\"Often mistakenly used when referring to double face cards, this mechanic originated in Kamigawa block\",Flip Cards\n" + "C,5,500,MTG,This base set is the first set designated with a numbered release.,Fourth Edition\n" + "D,1,100,Pokemon,\"\"\"Ay cutie, are you an electric rodent or can I get a...\"\"\",Pikachu\n" + "D,2,200,Pokemon,\"In the card game, there are this many basic energy types\",Nine\n" + "D,3,300,Pokemon,This fighting type pokemon's english name is partially inspired from a famous action comedy movie star.,Hitmonchan\n" + "D,4,400,Pokemon,\"In the original anime, albeit being a generation 2 pokemon officially, this is the first legendary Pokemon Ash Ketchum sees.\",Ho-oh\n" + "D,5,500,Pokemon,\"As of generation 9, this is the most common type of Pokemon\",Water\n" + "E,1,100,Board Games,This generic wooden piece is usually used to represent a person.,A meeple\n" + "E,2,200,Board Games,This board game changed a rule to allow proper nouns and it has been downhill ever since.,Scrabble\n" + "E,3,300,Board Games,This board game takes its name and theme from a famous road in Japan.,Tokaido\n" + "E,4,400,Board Games,The commonly used standard playing card deck has origins in this Europeon country. ,France\n" + "E,5,500,Board Games,\"This is what a super nerd calls a 20-sided die, also known as it's geometric name.\",icosahedron\n" + "F,1,100,\"Words that rhyme with \"\"piss\"\"\",A cat or a snake will perform this when upset.,Hiss\n" + "F,2,200,\"Words that rhyme with \"\"piss\"\"\",You may give one of these to someone you love.,Kiss\n" + "F,3,300,\"Words that rhyme with \"\"piss\"\"\",\"When class is over, the teacher will perform this action.\",Dismiss\n" + "F,4,400,\"Words that rhyme with \"\"piss\"\"\",\"If you stare into this for too long, it will stare back at you.\",Abyss\n" + "F,5,500,\"Words that rhyme with \"\"piss\"\"\",When you remember fondly.,Reminisce"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html