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

/
/
img

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 = "(gmai|ggmail|gmial|gmaol|gmil|iclould|gmeil|iclouds|icoud|hotmial|yahio|gmell|hotmil|gmailz|iclound|gmaio|gmile|gmaul|iclud|gmsil|gamil|ail|gnail|yhoo|gmal|gmaill|yaho|yshoo|gimail|gemail|gmail\\.com)\\.(com)$"; final String string = "gmai.com\n" + "gmial.com\n" + "gmaol.com\n" + "gmil.com\n" + "iclould.com\n" + "gmeil.com\n" + "iclouds.com\n" + "icoud.com\n" + "ggmail.com\n" + "hotmial.com\n" + "yahio.com\n" + "gmell.com\n" + "hotmil.com\n" + "gmailz.com\n" + "iclound.com\n" + "gmaio.com\n" + "gmile.com\n" + "gmaul.com\n" + "iclould.com\n" + "gmaul.com\n" + "iclud.com\n\n" + "gmsil.com\n" + "yahoo.con\n" + "gamil.com\n" + "gmail.co\n" + "ail.com\n" + "gnail.com\n" + "gmal.com\n" + "gail.com\n" + "yhoo.com\n" + "hmail.com\n" + "gmaill.com\n" + "yaho.com\n" + "yshoo.com\n" + "g.mail.com\n" + "yahoo.co\n" + "g-mail.com\n" + "gmail.comm\n" + "gmail.vom\n" + "icloud.con\n" + "hotmail.con\n" + "gimail.com\n" + "gmail.cim\n" + "gemail.com\n" + "gmail.com.com"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | 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