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

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?:[A-Za-z0-9!#$%&'*+\\/=?^_`\\{|\\}~-]+(?:\\.[a-z0-9!#$%&'*+\\/=?^_`\\{|\\}~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])"; final String string = "David Hills\n" + "Primeresllc@gmail.com\n" + " · Reply · 42w\n" + "Adrian Chu\n" + "badge icon\n" + "adrian@adrianchu.net\n" + " · Reply · 42w\n" + "Nick Bagoshvili\n" + "badge icon\n" + "Nick@ngbroofing.com\n" + " · Reply · 42w\n" + "Grace Wang\n" + "grace@ClarityPropertiesLLC.com\n" + " · Reply · 42w\n" + "Pete Venturo\n" + "That's my neighbor.\n" + " · Reply · 42w\n" + "Hom Teang\n" + "mrteang@gmail.com\n" + " · Reply · 42w\n" + "Derek Stephens\n" + "derek@summitreiholdings.com\n" + " · Reply · 42w\n" + "Julie K Clark\n" + "Julie@seattleinvestorsclub.com\n" + " · Reply · 42w\n" + "Alex Frankov\n" + "alexfrankov@hotmail.com\n" + " · Reply · 42w\n" + "Dawn Armstrong\n" + "Dawnarmstrong&hotmail.com\n" + "Outlook – free personal email and calendar from Microsoft\n" + "OUTLOOK.LIVE.COM\n" + "Outlook – free personal email and calendar from Microsoft\n" + "Outlook – free personal email and calendar from Microsoft\n" + " · Reply · 42w\n" + "Andrey Gulyy\n" + "Andreygulyyre@gmail.com please\n" + " · Reply · 42w\n" + "Viktor Bondarenko\n" + "viktor76@outlook.com\n" + " · Reply · 42w\n" + "Jeremy Macconnell\n" + "Sendmeyourdeals@foursqre.com\n" + " · Reply · 42w\n" + "A Suraphong Liengboonlertchai\n" + "Abuysellproperty@gmail.com. Thx 🙏\n" + " · Reply · 42w\n" + "Kellen Giroux\n" + "info@upraisedproperties.com\n" + " · Reply · 42w\n" + "Anthony Markiie Prado\n" + "Amprado@kw.com\n" + " · Reply · 42w\n" + "Jamil Newman\n" + "Westshoreinvestmentgroup@gmail.com\n" + " · Reply · 42w\n" + "Joe Clark\n" + "Josephclark10@gmail.com\n" + " · Reply · 42w\n" + "Nick Taitano\n" + "It's a great opportunity!\n" + " · Reply · 41w\n" + "Miao Jiang\n" + "mj@everestinvestments.net\n" + " · Reply · 41w\n" + "AJ Sheffield\n" + "aj@theoffmarketdeals.com\n" + " · Reply · 41w\n" + "Cindy Highsmith\n" + "Flyfreelw@gmail.com\n" + " · Reply · 41w\n" + "Steven Wang\n" + "stevenwproperties@gmail.com\n" + " · Reply · 41w\n" + "Miao Jiang\n" + "mj@everestinvestments.net\n" + " · Reply · 40w\n" + "Les Dreeson\n" + "ldreeson@listings.com\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (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