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

r"
"
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 = "(^S[A-Z]*\\ [0-9\\.]*$)"; final String string = "Aokia How doers\n" + "getmore done.\n" + "9615 DIAMOND CENTER DRIVE\n" + "MENTOR, OH 44060 (440)357-0428\n" + "3815 00061 42905 05/01/22 01:57PM\n" + "SALE SELF CHECKOUT\n" + "037155808113 DRAIN CRT <A> 15.88\n" + "CHROME FINISH PLASTIC TUB STOPPER\n" + "SUBTOTAL 15.88\n" + "SALES TAX 1.15\n" + "TOTAL $17.03\n" + "XXXXXXXXXXXX4651 DEBIT\n" + "USD$17.03\n" + "AUTH CODE 001059\n" + "Chip Read Verified By PIN\n" + "AID A0000000042203 US Debit\n" + "3815 05/01/22 01:57 PM\n" + "3815 61 42905 05/01/2022 9250\n" + "RETURN POLICY DEFINITIONS\n" + "POLICY ID DAYS POLICY EXPIRES ON\n" + "A 1 90 07/30/2022\n" + "****\n" + "DID WE NAIL IT?\n" + "Take a short survey for a chance TO WIN\n" + "A$5,000 HOME DEPOT GIFT CARD\n" + "Opine en español\n" + "www.homedepot.com/survey\n" + "User ID: H88 89914 86160\n" + "PASSWORD: 22251 86099\n" + "Entries must be completed within 14 days\n" + "of purchase. Entrants must be 18 or\n" + "older to enter. See complete rules on\n" + "website. No purchase necessary."; 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